[pianotech] Some Observations & Questions Regarding Partials &Inharmonicity

Ed Sutton ed440 at mindspring.com
Tue Mar 17 01:05:35 PDT 2009


Tyler-

Everything you've written below seems very perceptive and generally correct. There is no clear concensus about "fundamental beats." There are several possible explanations. You will eventually discover, for example, that the lower bass strings have almost no energy at the fundamental. The "sound" we hear may be a Fourier transform of higher partials, or it may be a neurological interpretation of complex information. (Obviously everything we hear is a "neurological interpretation of complex information." The neurological discoveries of the last 20 years are rapidly becoming common knowledge, and they will change our way of understanding everything, including tuning pianos.)

You seem to be a "natural" at this. Your understanding and perception exceed many people who have been at it (generally with the help of an ETD) for a long time. What resources are you using to learn?

I don't think you need to worry about "whole tone" listening or tuning. It's obvious you are hearing plenty of ways, and also thinking plenty of ways. "Whole tone" hearing is not clearly defined, and much of what we are writing about it is theoretical speculation. I recently heard a tuning by someone with "partial"hearing, and it is clear by what you write that you aren't stuck in "partial" hearing.

Are you a new member of PTG? Through PTG you would gain access to a lot of material, and a lot of colleagues.

Ed Sutton
  ----- Original Message ----- 
  From: Tyler Ferrari 
  To: pianotech at ptg.org 
  Sent: Tuesday, March 17, 2009 3:24 AM
  Subject: [pianotech] Some Observations & Questions Regarding Partials &Inharmonicity



  I have a few questions and observations I wanted to post, and hope to hear some replies.

  If a string is said to have a lot of inharmonicity, does that mean that all of its partials are always sharp? As the partial being listened to moves further away from the fundamental, does it get progressively and proportionately sharper (as if it were based on a simple multiplication of constant), or does it get 'exponentially' sharper depending on how much inharmonicity the string has? I'm finding when listening to certain strings that certain partials are sharper than others (in a single string). The octave partial in a single string may be quite close, but the 10ths (or 17ths) (for example) may be quite sharp. Am I hearing things, or can one partial be quite sharp compared to another?

  I don't quite know how to word that question, so if someone thinks they might have an answer if I can better clarify it, let me know.

  Next,

  It appears that most notes lower than C4 have partials that are more noticeable than others, as well as multiple audible partials. How does one choose where to split the difference, and choose which partial they are going to leave flat, or sharp? This becomes much more of an art when compared to the simple task of eliminating beat rates in the fundamental. Obtaining certain beat rates when listening to the fundamentals appears to be child's play compared to the task of choosing which partial to use as the reference for the quality of the unison, as well as the quality of an interval being played. Listening to the beat rate between fundamentals when playing an interval (at least in my case) does not provide me with the best sound. I usually need to add a slight beat to the interval to remove the issues with the partials that appear to be beating a rate much greater than the fundamental.

  It appears that at the cost of introducing a small beat rate into the fundamental, I can reduce the beat rate of the partials by a much larger amount. That seems like an advantageous trade-off. I don't believe that it is a proportional reduction. If I introduce (for example) .5 BPS into an octave, I may in fact reduce a particular partial's beat rate by 3-5 BPS. I'm certain that I'm hearing this, and it really makes a world of a difference when trying to objectively view the 'quality' of an interval.

  I've been reading the discussions and information that people have been posting regarding 'whole note' or 'whole tone' listening, or tuning. There's a lot of information and reference to information that I don't understand, but here is what I have to say about that.

  This may be a bold statement, but this is how it appears to me:

  If strings have inharmonicity, they cannot be properly tuned by listening to beat rates of fundamental tones alone. Maybe I'm totally dropping the ball on this one, but do some tuners only focus on the fundamental when tuning an interval or unison? If so, that REALLY does not seem right to me. In my case, the quality of the note is based on the fundamental beat rate as well as partial beat rates, and often sacrificing one or the other to obtain the best possible quality of tone.

  Eventually, I will learn the special circumstances with my piano well enough to be able to know how I want to tune certain unisons and intervals to compensate for the issues with the partials. That's just practice.

  But, I cannot imagine getting the point when I could walk into a customer's house, hear their piano for the first time and immediately have a good sense of how I need to tune the piano to best suit its particular situation regarding partial inharmonicity. A person who is doing that, is someone who I would consider a master-tuner. Is that the point when you become a Jedi Master Guru tuner, and you can simply tune a piano by looking at it? haha

  Thanks for reading my rant/journal on my findings and observations. I'm still a newbie, but I think I'm really getting the hang of things. I appreciate the criticism and support I'll receive from this message.

  -Tyler



------------------------------------------------------------------------------
  Communicate, update and plan on Windows Live Messenger. Get started today. 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090317/163d4cbc/attachment.html>


More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC