When I asked the question on stretching, I had a previous post in the back
of my mind. I have located that post in the archives and included it
below.
I'm still a little confused about the difference between "what the
theorists call 'stretch'" and the way a piano technician might view it.
Are we talking just about terminology, or are there different theories on
what stretch actually is?
Charles
*** post from Richard Moody, January 17, 2001 ***
Date: Wed, 17 Jan 2001 23:38:47 -0600
From: "Richard Moody" <remoody@midstatesd.net>
Subject: Re: Small temperament octave
I suspect that if the 2:1 octave is tuned beatless
then the double octaves will sound flat.
- -Robert Scott
If you mean two contiguious octaves it depends on various parts of the
piano whether the double octaves will "sound" flat. Piano tuninig is done
first and last by beats, not by sound or intonation. Of course "the
sound" has to be agreeable after the tuning.
When aurally testing double octaves, the 4th partial of the bottom
note will sound with the 1st partial of the upper note. How sharp the 4th
partial is, is how "sharp" the 1st partial will be when "in tune". This
is what the theorists call "stretch" but not piano tuners. We realize
theory says because of inharmonicity a beatless octave may indeed be
"stretched" from mathematical perfect ratios.
Stretch for tuners is how many beats sharp an octave can be before it
becomes "objectionable", or what is needed to satisfy asthetic concerns.
This of course is a judgement call and why some call tuning an art.
After all, what is art but producing what other people will appreciate?
---ric
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