Just happened upon this old thread.
So fascinating. My biggest regret in piano tuning is not meeting Virgil.
I'd like to make some comments on the unison drifting though that I hope will clarify some important misconceptions. I'm working on a submission for PTJ called Piano Tuning Myths and I think I've found another one:
"The final pitch of a trichord can be lower than the single string"
Technically False!My myths are based of disproving statements that are not 100% correct, and therefore cause confusion, and this statement which has been voiced by everyone with an opinion on it above, is false because it is not 100% correct, including the explanations of why it occurs.
Let me share my path to the understanding of this phenomenon.
At first, probably from reading Virgil's book, I was under the false impression, as many here have voiced, that the final pitch of a trichord can occasionally go flat. I had observed this in my own tuning.
In presenting this on various forums, someone mentioned the Weinreich Effect.
During a presentation at my local PTG chapter, I was trying to demonstrate this and, lo and behold, the final pitch went
sharp. Obviously this threw me for a loop.
In my attempt to find out what the heck was going on, I contacted Professor Gabriel Weinreich and he corrected me. When I said the pitch is supposed to go flat, he said, "Not exactly. The pitch could go flat, or it could go sharp, and there is no way to tell."
Since then I have created a video demonstrating the phenomenon, and I have also written an article that contains data from experiments that confirms that,
"The final pitch of a trichord can stay the same, go down, or up, and it is unpredictable."
From this observation, any instruction to "Tune a string slightly sharp first in order to anticipate the drop" is misguided and will cause confusion when the final pitch either doesn't change, or rises.
Here is a link to my video:
http://howtotunepianos.com/2016/02/12/unison-drift/In my correspondence with Professor Weinreich, who is still alive at 91 years old, he said of the video above:
"For a particular string attached to a particular soundboard, it could go either way. Which is exactly what your beautiful videos show."
(I have attached his entire email response for those interested, below.)
Here is a link to the article in March 2016:
https://my.ptg.org/viewdocument/ptj-2016-03?CommunityKey=7207b7a3-572f-4e55-8469-ebe01384719b&tab=librarydocumentsIn the article I refer to a technique I have defined as "Double String Unison". I do not say "a technique I have invented" because this technique has been used by many other high level technicians before me and I have just systematized its use. It is in effect the "Unison Cracking" that was mentioned above, but at a much higher level; I am tuning the whole piano from beginning to end using unison cracking.
Email response from Professor Gabriel Weinreich:
"Dear Mr Cerisano,
As I recall our previous conversation, it concerned the tuning of three 'unison' strings. We consider the situation where two of the three strings are damped and the third is adjusted until its frequency is, by some appropriate criterion, "correct". Now we remove the damping of a second string of the triplet, and notice that although we haven't touched the one we just tuned, its frequency has shifted. The question is: in what direction did it shift, up or down?
If that is not the question you had in mind, please correct me.
If, however, it is indeed the question you had in mind, then my answer is that, on the basis of the data given, it could go either up or down. It all depends on the impedance of the bridge at that frequency; more specifically, it depends on the precise frequency response of the soundboard (to which the bridge is attached). The bridge, of course, moves very little, but still enough to get a precisely tuned string out of tune by a slight amount.
Up or down? That depends on exactly how the string frequency lines up with the resonances of the soundboard. For a particular string attached to a particular soundboard, it could go either way. Which is exactly what your beautiful videos show.
Best regards, Gabriel Weinreich"
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Mark Cerisano, RPT
http://howtotunepianos.com------------------------------
Original Message:
Sent: 08-24-2018 14:11
From: Chris Chernobieff
Subject: Wanting a copy of Virgil Smiths Tuning book
I'm still searching for a copy btw.
Schaff no longer carries it. Since I had them on the phone, i thought I'd try the Rick Butler book and video.
Discontinued as well.
Original Message------
I just got back from 3 days in ultra quiet and peaceful lake surroundings in northern Vermont. No internet, no cell phone, no messaging...Ahhhhhh...😊
So, as I see it, it doesn't really matter to me what the actual "cause" of the Weinrich effect is...it happens. And it happens enough (not 100%) to warrant having a method to deal with it, which is what Virgil did.
My current method (which I have found very effective) is to put the first string of the unison (let's just say the left) where I want it, then tune the next string slightly higher (with a "micro-beat" [I forget now who coined this]). This tends to influence the first string UP (counteracting the WE). Then I tune the 3rd string slightly higher (micro-beat) which sometimes influences it even higher (but sometimes not). Now I listen to the octave. If I'm happy I move on. If not I mess with it till I'm happy.
Occasionally the WE is so strong between the first and second strings that I have to literally induce a beat into the octave first, which the second string will bring down to near where I want it. Then on to the 3rd to see what that does.
I have proven to myself over and over that this is all quite real by using Tunelab to measure the first, then the second, then the combined effect, then on to the 3rd. The degree of power of the WE varies from note to note and piano to piano.
Now, I have also found that in this procedure I may hear "movement" in the unison a tad too much. I have repeatedly found that if I go back to the MIDDLE string and manipulate that ever so slightly I can very often silence that movement while still maintaining its integrity (and bloom) and the ascending pattern in the strings.
Sometimes the piano will simply not allow me to do this routine and it wants dead-on unisons. Fine...then that's what I do (still compensating for whatever WE happens to be present in that piano).
This is my current strategy for dealing with the issue. I am certainly open to other methods that are employed, and would like to hear them.
Pwg
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Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
Original Message:
Sent: 08-21-2018 16:46
From: Keith Roberts
Subject: Wanting a copy of Virgil Smiths Tuning book
What I'm saying is Dr Sanderson measured the Fundamental or 1st partial and detected no change in pitch.
He then changed to measure the 2nd partial and no change in pitch.
He changed to the 4th partial and detected a drop in pitch.
Virgil's aural check to produce a beat that we could hear the difference must have been based on the 4th partial. We assume the other partials had to go flat if the 4th partial does,,,, The RCT tunes by the partials,,,,, I get different readings if I stop the spinner or if I measure the note individually.
This was a Steinway B. Other pianos might have different measurements.
I happened to have Dr Sanderson wander into the room I was in after the class and I asked him if it was interference at the bridge or direct air wave interference in the close proximity of the wires. He got excited and didn't have an answer,,, smart man.
In case you were wondering I scored in the top 1% in the nation on the math part of the SAT. Then I had 5 quarters of math, 3 of physics, 3 of chemistry, 2 of mechanical engineering at UC Santa Barbara,,, not that I remember any of it,,,,, but it helps when listening to technical discussions to have that intuitive sense. No, I didn't have it backwards what I saw. Verification through duplication is the only way to really know what the reality is. But then there are always exceptions,,,
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Keith Roberts
owner
Hathaway Pines CA
209-728-2163
Original Message:
Sent: 08-18-2018 11:51
From: Richard West
Subject: Wanting a copy of Virgil Smiths Tuning book
Maybe I'm not visualizing what you're saying, Keith, but it seems to me you have it backwards. The important takeaway from Virgil and Dr. Sanderson is that as you tune the unison, the pitch drops every so slightly. That's why it's important to tune the first string on the high side so that when it drops as the unison is brought in, the final unison position is still high enough to be good. That's where Virgil's "cracking the unison" is so important to final accuracy. That procedure allows the tuner to make the finest of corrections to end up with not only a good unison, but a unison that is properly placed to make it fit in with the tuning universe of a particular piano.
When you say that you don't like a too-stretched-out treble, it seems to me that you have to actually start with the first string being "too stretched out" so that the final placement of the unison isn't stretched out as the other two strings are tuned.
Also, I think it is interesting the degree of accuracy that Virgil was able to show. All of us aural tuning people should stand up for the power of multiple checks and the aural tuning accuracy. The questions we have to continually deal with is how much stretch is enough, and how much time are we going to spend trying to be perfect and when are we going to quit when it's good enough meaning not only accurate but stable.
Richard West
Original Message------
I sat next to Dr Sanderson while watching Virgil tune. Dr Sandersan was supposed to scientifically verify the claim that 2 strings played together are slightly flat compared to one string,
Virgil tuned the two wires. Played separately they were exactly the same. Aural checks and The accutuner agreed.
Played together, Virgil showed the aural checks that indicated it was slightly flat.
Dr Sanderson couldn't find the difference until he went to the 4th partial and that partial was flat in comparison.
Seems to me that might be why I don't like a too stretched out treble. The 4th partial from the tenor wouldn't line up with the treble.