Pianotech

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Fundamental probably exists, just very weak and hard to hear and feel.

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Parker, I think that it definitely exists as a string vibration. The soundboard is just not able to pick it up and amplify it. at least this is how I understand it.

Fundamental probably exists, just very weak and hard to hear and feel.

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

The soundboard clearly amplifies all frequencies but with different amplitudes. Read Olson's classic work on Sound Engineering.

Parker, I think that it definitely exists as a string vibration. The soundboard is just not able to pick it up and amplify it. at least this is how I understand it.

Fundamental probably exists, just very weak and hard to hear and feel.

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

It is called the phantom fundamental.  The true fundamental may be a fiction, but it sure is a useful one.  

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Interesting. 

But, using various FFT analyzers, I have analyzed the waveform produced by pianos of different sizes in an attempt to identify acoustical energy at the fundamental pitch of the lowest notes. If it is there it is getting lost in the noise of the system.

ddf

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Question: Is the ability to hear by inference the fundamental of a low bass tone a spontaneous phenomenon or is it something that is learned?

Interesting. 

But, using various FFT analyzers, I have analyzed the waveform produced by pianos of different sizes in an attempt to identify acoustical energy at the fundamental pitch of the lowest notes. If it is there it is getting lost in the noise of the system.

ddf

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

I find it interesting that several large animal species communicate (in part) in the infrasonic range (below 20hz) with some elements in the 20-40hz range. Often these carry long distances (both in air and water). 

I wonder if it's possible that, with even a minute trace of these frequencies, our ear/brain can sense it, and thus trigger our ability to infer or supply the low fundamental frequencies even though they are technically inaudible.

Just thinking 🤔 

Peter Grey Piano Doctor 

Question: Is the ability to hear by inference the fundamental of a low bass tone a spontaneous phenomenon or is it something that is learned?

Interesting. 

But, using various FFT analyzers, I have analyzed the waveform produced by pianos of different sizes in an attempt to identify acoustical energy at the fundamental pitch of the lowest notes. If it is there it is getting lost in the noise of the system.

ddf

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

These intellectual excercises are great and all, but thats it. Not how you build great soundboards or the piano as a whole. These theories have been out there for so long that they have to be considered dinosaur ideas by now when considering that most pianos are made badly and have to be heavily worked by experts like yourselves to make them presentable.  Example, i buy the the lightest hammers i can find, and i still spend all day getting them down to the proper weight. Ridiculous.

I've spent the last  20 years +  meticiulously honing my craft in the shop to make my customers happy. Thats a more realistic, powerful way to learn how to make high a quality product like a soundboard perform in an awesome manner. If a worthy invention is going to come along, its most likely going to come from that foundation rather than the endless recyling of intellectualism.

-chris

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Chris,

I don't consider myself young at 39, but most of my clients and a number of other techs insist that I am. 🤣 

I am fairly new to the field of piano technology, so this is not a debate/conversation I've heard endlessly. Speaking for myself, my curiosity about how the piano works has given me a better understanding of the instrument as a whole which in turn helps me make decisions, and at a number of points (both in rebuilding and tuning in particular), think outside the box, as I know you do.

It is unclear to me whether or not my curiosity exists only in the realm of intellectualism in conversations like these, since I have yet to see where the information takes me. Part of my curiosity about this subject is because I tune unequal temperaments exclusively now. My Yamaha C5 has been my workhorse since 2001. Every tiny change I make does not go unnoticed- this instrument has been an extension of me for 24 years. When I changed the tuning, the bass became much more "alive," even with the now 45 year old strings. I know that the tuning method capitalizes on inharmonicity, physics and psychoacoustics. This conversation is especially intriguing to me because the better we can understand the interaction of these phenomena, the more potential I have to allow the piano to give me what I want. 

These intellectual excercises are great and all, but thats it. Not how you build great soundboards or the piano as a whole. These theories have been out there for so long that they have to be considered dinosaur ideas by now when considering that most pianos are made badly and have to be heavily worked by experts like yourselves to make them presentable.  Example, i buy the the lightest hammers i can find, and i still spend all day getting them down to the proper weight. Ridiculous.

I've spent the last  20 years +  meticiulously honing my craft in the shop to make my customers happy. Thats a more realistic, powerful way to learn how to make high a quality product like a soundboard perform in an awesome manner. If a worthy invention is going to come along, its most likely going to come from that foundation rather than the endless recyling of intellectualism.

-chris

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Chris,

I don't consider myself young at 39, but most of my clients and a number of other techs insist that I am. 🤣 

I am fairly new to the field of piano technology, so this is not a debate/conversation I've heard endlessly. Speaking for myself, my curiosity about how the piano works has given me a better understanding of the instrument as a whole which in turn helps me make decisions, and at a number of points (both in rebuilding and tuning in particular), think outside the box, as I know you do.

It is unclear to me whether or not my curiosity exists only in the realm of intellectualism in conversations like these, since I have yet to see where the information takes me. Part of my curiosity about this subject is because I tune unequal temperaments exclusively now. My Yamaha C5 has been my workhorse since 2001. Every tiny change I make does not go unnoticed- this instrument has been an extension of me for 24 years. When I changed the tuning, the bass became much more "alive," even with the now 45 year old strings. I know that the tuning method capitalizes on inharmonicity, physics and psychoacoustics. This conversation is especially intriguing to me because the better we can understand the interaction of these phenomena, the more potential I have to allow the piano to give me what I want. 

These intellectual excercises are great and all, but thats it. Not how you build great soundboards or the piano as a whole. These theories have been out there for so long that they have to be considered dinosaur ideas by now when considering that most pianos are made badly and have to be heavily worked by experts like yourselves to make them presentable.  Example, i buy the the lightest hammers i can find, and i still spend all day getting them down to the proper weight. Ridiculous.

I've spent the last  20 years +  meticiulously honing my craft in the shop to make my customers happy. Thats a more realistic, powerful way to learn how to make high a quality product like a soundboard perform in an awesome manner. If a worthy invention is going to come along, its most likely going to come from that foundation rather than the endless recyling of intellectualism.

-chris

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Tim! 

Keep asking these questions! It may seem tiresome to the old fogeys, but it is essential that we pass the knowledge on.  Your asking the question lets us know that we haven't spread the knowledge to everyone. Yet. 

Chris,

I don't consider myself young at 39, but most of my clients and a number of other techs insist that I am. 🤣 

I am fairly new to the field of piano technology, so this is not a debate/conversation I've heard endlessly. Speaking for myself, my curiosity about how the piano works has given me a better understanding of the instrument as a whole which in turn helps me make decisions, and at a number of points (both in rebuilding and tuning in particular), think outside the box, as I know you do.

It is unclear to me whether or not my curiosity exists only in the realm of intellectualism in conversations like these, since I have yet to see where the information takes me. Part of my curiosity about this subject is because I tune unequal temperaments exclusively now. My Yamaha C5 has been my workhorse since 2001. Every tiny change I make does not go unnoticed- this instrument has been an extension of me for 24 years. When I changed the tuning, the bass became much more "alive," even with the now 45 year old strings. I know that the tuning method capitalizes on inharmonicity, physics and psychoacoustics. This conversation is especially intriguing to me because the better we can understand the interaction of these phenomena, the more potential I have to allow the piano to give me what I want. 

These intellectual excercises are great and all, but thats it. Not how you build great soundboards or the piano as a whole. These theories have been out there for so long that they have to be considered dinosaur ideas by now when considering that most pianos are made badly and have to be heavily worked by experts like yourselves to make them presentable.  Example, i buy the the lightest hammers i can find, and i still spend all day getting them down to the proper weight. Ridiculous.

I've spent the last  20 years +  meticiulously honing my craft in the shop to make my customers happy. Thats a more realistic, powerful way to learn how to make high a quality product like a soundboard perform in an awesome manner. If a worthy invention is going to come along, its most likely going to come from that foundation rather than the endless recyling of intellectualism.

-chris

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

The tiresome old fogey thing is actually a mischaracterization. Bruce Lee said " Adapt what is useful, and reject what is useless". Everyday piano technology is useful knowledge that should be shared. The statement "the soundboard fundamental and the mind fills in the blank stuff"-- who cares? Totally useless info. I dont really care, but its probably flat out wrong anyways. 

When you do a Chladni test (ancient technology) you can see the fundamental thats produced. Its about 55hz (A1).

-chris

Tim! 

Keep asking these questions! It may seem tiresome to the old fogeys, but it is essential that we pass the knowledge on.  Your asking the question lets us know that we haven't spread the knowledge to everyone. Yet. 

Chris,

I don't consider myself young at 39, but most of my clients and a number of other techs insist that I am. 🤣 

I am fairly new to the field of piano technology, so this is not a debate/conversation I've heard endlessly. Speaking for myself, my curiosity about how the piano works has given me a better understanding of the instrument as a whole which in turn helps me make decisions, and at a number of points (both in rebuilding and tuning in particular), think outside the box, as I know you do.

It is unclear to me whether or not my curiosity exists only in the realm of intellectualism in conversations like these, since I have yet to see where the information takes me. Part of my curiosity about this subject is because I tune unequal temperaments exclusively now. My Yamaha C5 has been my workhorse since 2001. Every tiny change I make does not go unnoticed- this instrument has been an extension of me for 24 years. When I changed the tuning, the bass became much more "alive," even with the now 45 year old strings. I know that the tuning method capitalizes on inharmonicity, physics and psychoacoustics. This conversation is especially intriguing to me because the better we can understand the interaction of these phenomena, the more potential I have to allow the piano to give me what I want. 

These intellectual excercises are great and all, but thats it. Not how you build great soundboards or the piano as a whole. These theories have been out there for so long that they have to be considered dinosaur ideas by now when considering that most pianos are made badly and have to be heavily worked by experts like yourselves to make them presentable.  Example, i buy the the lightest hammers i can find, and i still spend all day getting them down to the proper weight. Ridiculous.

I've spent the last  20 years +  meticiulously honing my craft in the shop to make my customers happy. Thats a more realistic, powerful way to learn how to make high a quality product like a soundboard perform in an awesome manner. If a worthy invention is going to come along, its most likely going to come from that foundation rather than the endless recyling of intellectualism.

-chris

The extra notes of the Imperial were created for Busoni to be  able to play his Bach Transcriptions more convincingly.

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------

Yes, an interesting conversation. 

Question: What qualities would a string/soundboard combination have to have in order for it to be able to actually reproduce the fundamental of a low bass string? And, would actually being able to hear the fundamental of a low bass string be a desirable quality of a piano? 

Harry Partch built a percussion instrument called the Marimba Eroica. Slightly larger than his Bass Marimba. The Marimba Eroica is quite large, with the lowest note being about F0, at about 22 Hz. (A0, by comparison is about 27.5 Hz.) I've "heard" the Marimba Eroica in concert and even considering the partials it may be reproducing that note isn't so much heard as it is felt. It's loud but you feel it in your chest and see it in your clothes fluttering more than you can actually hear it. 

Interesting discussion. I thought I would see what chatgpt.com had to say about the topic. People warn about the potential for "hallucinations" from AI systems – see what you think – probably depends on the subject matter. If you have follow-up questions, the system remembers your context – go to it -- including asking for references and further justification, etc. Challenge it. Regards, Norman

Q: I am a piano tuner in a discussion group about fundamental frequencies for a grand piano. For the lowest notes on a grand piano, can the fundamental (first partial) be heard, or is it too weak?

A: Great question - and one that touches on both acoustics and psychoacoustics.

For the lowest notes on a grand piano (say, A0 to around C1), the fundamental (first partial) is indeed present, but it is typically very weak acoustically and often not perceptible to the human ear as a distinct pitch.

Why the fundamental is weak:

• String length vs. tension tradeoff: In the bass, the piano strings are long and thick, but still not long enough to produce a strong, low-frequency fundamental at practical tension. As a result, the string vibrates in such a way that higher partials (especially the 2nd through 6th) carry most of the acoustic energy.

• Soundboard coupling: The large wavelength of very low frequencies (e.g., A0 at ~27.5 Hz has a wavelength of ~12.5 meters) means the soundboard doesn't resonate efficiently at these frequencies. It radiates the higher partials more effectively.

Psychoacoustic perception:

• Even if the fundamental is very weak or missing, the ear can infer the pitch through the harmonic series. This is the missing fundamental phenomenon - our brain reconstructs the pitch based on the spacing of upper partials.

• Thus, listeners perceive the correct pitch even when the fundamental is inaudible or absent.

In practice:

• If you analyze the waveform (e.g., with a spectrum analyzer), you will see the fundamental is present but with very low amplitude.

• A technician or tuner might describe the fundamental as "not speaking clearly" or being "lost," especially on older instruments or ones with poor bass string performance.

Would you like a spectrogram of a bass piano note to see how the partials stack up visually?

------------------------------
Norman Brickman
Potomac Piano Service
Potomac, Maryland
potomacpiano@verizon.net
https://potomacpiano.com
(301) 983.9321

Original Message:
Sent: 05-08-2025 10:27
From: Parker Leigh
Subject: Lowest fundamental

I think you need to define "fundamental."  Even large pipe organs have week fundamentals at 16 hz and very few loadspeakers are able to reproduce that.

I contend that most pianos have at least some fundamental down to 60-70hz, perhaps lower for some large concert grands.  Our ear supplies the rest.

Mason & Hamlin pianos seem to have more fundamentals than Steinways in part due to rim structure and soundboard thickness.

------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865

Original Message:
Sent: 05-08-2025 09:03
From: Tim Foster
Subject: Lowest fundamental

Del, thanks for weighing in! I thought about what you said after going to a presentation with Jason Cassel last Saturday, where he isolated groups of partials from a single note (F4, I believe). I think he grouped partials 1-9, 10-19, 20+, or something close to that. When he filtered out the lower nine, though the quality sounded different, I felt like I was hearing the fundamental with each higher group, even though it wasn't actually present. That was the closest I've come to experiencing what you talked about. 

After making soundboard repairs to my latest rebuild (5'1" Schomacker baby, 1908), and before installing the plate, I recorded the "fist test" into my iStroboSoft spectrogram. The screen shot below shows multiple "fist bumps" in a fairly steady pulse. I really don't know how to read the info I'm seeing, but I find it interesting how it seemed to resonate most powerfully around 60-70 hz. 

Have you found a region where the fundamental noticeable drops off in most pianos, or specific piano types/sizes?

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 05-08-2025 02:00
From: Delwin Fandrich
Subject: Lowest fundamental

I've verified this several times with pianos of various sizes; at least to my own satisfaction. I've used both accelerometers and measurement microphones to pick up the sound energy. I've even tried driving the bridge of a concert grand with low frequency vibration shakers. It's not there. (Well, you can force it using far more input energy than is available from any piano string, but that doesn't count.)

The lowest (theoretical) fundamental frequency of the piano is 27.5 Hz. That's pretty low. The structure of the soundboard and bridge mechanism coupled with the design of the strings (including the backscale) makes it simply impossible for the production of any audible tone at that frequency. Picture what it takes for the sub-woofer in a high-end audio system to come close to this. 

What we hear is our brains filling in what our ears pick up from the various harmonics that are produced. 

ddf

------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]

Original Message:
Sent: 05-08-2025 00:47
From: David Stocker
Subject: Lowest fundamental

As Del related the story to me, when he was at Baldwin he attached extremely sensitive accelerometers to the bass bridge. There was no detectable energy at the frequency of the fundamental on most pianos. 

------------------------------
David Stocker, RPT
Olympia WA

Original Message:
Sent: 05-06-2025 23:16
From: Tim Foster
Subject: Lowest fundamental

Hello,

While at last year's convention, Del Fandrich blew my mind when he mentioned that the soundboard cannot produce the fundamental of the lower notes and that our brains hear the partials coming off of these strings and "fill in the blanks." But now I'm wondering, what are the lowest fundamentals the piano can produce and does this vary from piano to piano?

Thanks!

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074
------------------------------