CAUT

  • 1.  Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-05-2024 22:39

    In order to make 'sound' you have to 'move air' and so the string by itself moves very little air. The soundboard moves orders of magnitude more air. 

    Think of the piano as a mechanical-to-acoustic transducer. It transforms mechanical vibration into acoustic waves.

    Now think of a microphone as an acoustic-to-electrical transducer. It transforms acoustic waves into electrical signals.

    Now think of the PianoSens device. It BYPASSES THE ACOUSTIC DOMAIN. It DIRECTLY transforms mechanical movement (string movement) into electrical signals.

    Hence, there is no transformational loss. It is repeatable and accurate.

    Think that the soundboard has an infinite number of acoustic responses depending on the position of the mic or the listener. PianoSens removes all that uncertainty. It takes an infinite number of possible transfer functions down into only ONE transfer function.

    Try it and you will see. It is 'invariant' by design.

    Steven Norsworthy

    PianoSens.com



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    Steven Norsworthy
    Cardiff By The Sea CA
    (619) 964-0101
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  • 2.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-05-2024 23:49
    More....

    On 1/5/2024 7:39 PM, Steven Norsworthy via Piano Technicians Guild wrote:
    > In order to make 'sound' you have to 'move air' and so the string by itself moves very little air. The soundboard moves orders of magnitude more air.
    >

    Stipulated.

    > Think of the piano as a mechanical-to-acoustic transducer. It transforms mechanical vibration into acoustic waves.
    >

    Ditto.

    > Now think of a microphone as an acoustic-to-electrical transducer. It transforms acoustic waves into electrical signals.
    >

    Ditto.

    > Now think of the PianoSens device. It BYPASSES THE ACOUSTIC DOMAIN. It DIRECTLY transforms mechanical movement (string movement) into electrical signals.
    >
    > Hence, there is no transformational loss. It is repeatable and accurate.
    >

    Yes. So, within certain, highly defined limits, it senses ("picks up")
    certain aspects of a particular pitch from a particular string.

    There are still variables which are not accounted for in this model.
    One might be the feedback (to the string) from the soundboard and bridge
    which the model otherwise seeks to eliminate. Such feedback, in
    addition to other artifacts, would probably include whatever string
    termination issues might be present, &c.

    > Think that the soundboard has an infinite number of acoustic responses depending on the position of the mic or the listener. PianoSens removes all that uncertainty. It takes an infinite number of possible transfer functions down into only ONE transfer function.

    This sounds like a solution in search of a problem. To be clear,
    there's nothing wrong with that...at all. Rather, I find myself
    wondering what the real-world use-model might be.

    Further, I am mindful that most pianos are not designed to be listened
    to in close proximity, certainly not closer than the bench on which the
    player sits. Some "scales" have been designed with varying volumes and
    shapes of space in mind. In the case of some of those scales, the
    "tone" of the piano does not befin to actually "gel" aurally until the
    "ears" of the mic/hearer are sometimes as much as fifteen to twenty feet
    away. At whatever the "listening distance" might be, the "aural
    presentation" (for lack of a better term) of a given piano is very
    different from what it might be in close proximity (to the
    strings/bridges/soundboard).

    That "close micing" became (and remains) so popular has as much to do
    with trying to recreate the sense of hearing the piano from the position
    of the player as anything else. (A "Listener's Choice" selection of
    major concerto recordings in which one hear
    PIANO...<...(...and...orchestra...)...>...makes this point.) The
    observation here is that, even at that relatively close proximity, the
    "ear" of the microphone(s) employed in the recording (without regard to
    type ,number, or placement) are still "hearing" the sound of the piano
    with all of the intricacies of aural presentation which this system
    appears to be working to eliminate.

    I see that there is another post....more to follow....

    Horace




  • 3.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-06-2024 07:30

    The vibrating string exists in a flexing environment, the soundboard/bridge/piano, which exists in a surrounding environment (the piano can transduce sound waves into motion of strings), and all of this is further varied by the energies that are being entered into the piano by whatever strings are vibrating. So, once things are happening, everything is to some degree variable. 

    Nevertheless, there is fair argument to begin with the vibrating of a just struck single string or unison.

    Assuming a here-to-fore unobtainable accuracy of tuning has been obtained, is it worth asking how long this accuracy will be maintained to a degree that concerned listener can say "Wow!" And how much it will add to the cost of piano maintenance that is becoming more and more a luxury service. Will it help children learn to play better?

    Digital technologies offer us this question in many places. At best it is wonderful; scaling and touchweight programs, for example. At some point we must admit that actual reality does not allow easy manipulations to ever finer decimal points. Since I'm currently working with fluorocarbon strung instruments, I don't need to answer this question about PianoSens, but I'll enjoy watching.



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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 4.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-06-2024 08:15
    In the end, as I show in my presentation class, move the mic position and observe a one cent change in the indicator. Is that acceptable? Which position do you believe in? One-cent errors will accumulate and propagate in the overall tuning of the instrument. Why not a system that is invariant?




  • 5.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-06-2024 09:05

    Steve-I have no argument with the success of your technology at achieving a new extreme of accuracy.

    But can it be that we are entering the Clipper Ship Era of piano tuning? 



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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 6.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-06-2024 09:41
    Paul McCloud coined the term of my sensor: “Rising the Bar”

    The problem in the past is that highly qualified engineers are getting paid handsomely to work on Comms for commercial and military systems, not piano waveforms. Signal Processing engineers are a special breed. Waveform analysis is fundamental to all Comms, and the piano produces waveforms and communicates as a real comm system.

    Engineers fall into two types:

    (1) Those who solve fundamental problems through research, getting to the real essence of the problem, the root causes.

    (2) Very good at executing known things and making incremental improvements.

    A third type in the food chain would be Technicians who go into the field and take known tools and do the best with what they have.

    Hope that helps. I started my engineering career at Bell Labs. It was the finest research lab in history, all would agree. The culture I absorbed there and my natural research abilities were a perfect match. I rose to a department head in just a few years after making major breakthroughs in audio data converters. You can to to my engineering website rf2bits.com if you want to read more. However, I started out as a music professor and orchestral trombonist and conductor (and a piano ‘minor’). As of today, I have over 137 patents (US and International) to my name. Every time you use a cell phone you are using numerous of my patents from Bell Labs, STMicro, and Qualcomm. I am now ‘getting back’ to music and practice my Fazioli F308 about 2-3 hours per day. I can play the ‘major literature’ and have excerpts you can hear on my personal YouTube channel.

    Hope all of this helps you understand me better. I am driven to push the envelope and God just wired me this way.

    Kindly,
    Steve




  • 7.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Registered Piano Technician
    Posted 01-06-2024 10:36

    We are asking the question, "Will this new technology make a difference to our clients?  Will they be able to tell that you have done a better job?"  Or, another question is, "Is it worth my time to create a better tuning, if I have to increase my skills and invest more effort to achieve it?"  When I started using a sensor and Pianoscope, I started getting unsolicited emails and messages commenting on how nice the piano sounded than before.  One comment from a touring artist said she just couldn't stop playing her piano (Ste.B).  People do notice the difference, and that translates to more referrals and builds your reputation. 

    My main focus in tuning has always been to create as perfect unisons as I possibly can.  It's like the "holy grail", and part of my motivation to achieve it.  I know there are some, perhaps many, that advocate for a more "blended" type of unison and believe that is more interesting and desirable.  It is a choice, perhaps an artistic choice, to create a type of "piano vibrato",  Or, it could be seen as a "sour grapes" scenario, where unisons are going to go out anyway in a short time, so don't obsess about making them perfect.  If blended unisons are acceptable, then why do we have unison tuning as part of our exam?  And if this unison matching technique is preferable, exactly how far off is acceptable? 

    As far as the overall tuning with an ETD, if we now know that there can be 1 cent errors due to microphone placement and errors due to unwanted resonances, is that really better than tuning by ear?  And how accurate are some ETD's that use a single partial, vs others that use multiple partials?  Many years ago, using my Accutuner, I couldn't understand why the other ETD apps did not agree with my machine.  I still wonder, but understand the differences in stretch, tuning styles, etc.  We still use our ears as a final arbiter, even if our device insists that it's perfect.  False beats and mismatched strings are still the bugaboo of piano tuning, no matter whether you use your ears or an ETD.  The ETD makers are well aware of this, but working on it.. 

    As far as myself, using the latest tools, I have had to increase my skills to be able to achieve almost perfect unisons, heretofore unattainable without them.  I'm very pleased to play intervals across the piano that are more clean than ever, and proud that I did my best job.  Now that I've gone this far, I can't stand to hear the slightest beat in a unison, and it's nice to know that I can use my tools to check each individual string if necessary with my ETD to correct it, rather than doing it by ear to figure out which string is off.  If blending your unisons is your choice, at least we can agree that one string should be dead-on, and the others matched to it, however you want to do that. 

    My final thought is, piano tuning by aural methods has been going on for centuries, and for the most part accurate enough to satisfy artists and audiences for all those years.  Then came the Strobotuner, which still required aural skills.  The Sight-0-Tuner, Accutuner, and all the apps now available have made it easier and perhaps faster and more accurate, but has it really made a difference to the piano public?  It's a matter of perception.  If they don't hear it, does it matter to them?  I hope they do hear that it's better, and recognize that they've never heard their piano sound like that before.  That's the perception I want.



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    Paul McCloud, RPT
    Accutone Piano Service
    www.AccutonePianoService.com
    pavadasa@gmail.com
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  • 8.  RE: Piano As A Transducer (regarding acoustic vs string movement)

    Posted 01-06-2024 11:07
    Ed Sutton:

    I would be pleased to offer doing my class presentation to your local monthly PTG group, or any private group of your peers and experts. I promise it will be worth your while. The research I have done cannot be found in the Journal of Acoustic Society of America. It Is ‘new’ and I have not submitted formal papers (yet). I can do the session on my zoom account to any group on the globe. I love teaching and I am a very engaging presenter.

    Kind regards,
    Steve