How We Hear

[Jenneetah]

Hi Don,

At 7:13 PM -0400 10/24/04, Don wrote:
>If as I said, I "tune" a 7th partial, using an etd, then the unison is
>*not* clean, or rarely is. I have not taken the time to investigate which
>partial the "noise" was in, nor tried to measure "widths".

We probably will need to get to a piano to straighten this out, 
although piano work for either of us is not going to come to a 
screeching halt until we can.

On my first two pianos today, a 30-year-old Yamaha G2 and a 
20-year-old Steinway S, I confirmed that the 7th partial was as 
effective a means of zero-beating the 1st partial, as it ever has 
been for me. Certainly wrapped strings, with the greater number of 
variables in their inharmonicity formula are far more easily 
disturbed than the plain steel strings. But even here, the beating 
partials were likely to be an octave (or even higher) above the 7th 
partial, rather than anything below the 7th partial.

I also tried Andre's suggestion of tuning quietly, using as a 
technique having my finger at a dead stop in contact with the key and 
accelerating the key no faster than is possible with a 3/8" stroke of 
the forearm. (You quickly learn not to aim for loudness with that 
short a stroke. The forearm simply can't accomplish anything in 3/8"; 
the key bottoms out too soon. It's like sitting down for a 
harpsichord tuning after a whole music department's worth of practise 
room pianos. "....This instrument is supposed to be played quietly.")

So with a mezzo blow, the 7th came through just as clearly as with my 
normal tuning blow, and I had plenty of sustain time to work with the 
7th (easily 12-15 seconds in the 3d octave). Less stress on the ears 
and on the left hand, and although the facts about strings friction 
and tuning pin grip aren't altered by the softer blow, in this 
working situation the hand-on-the-hammer processes feel much more 
relaxed. Test blows revealed no difference between loud and quiet 
tuning.

The 7th partial, even on these two mildly warm sounding pianos, was 
usable partway through the 4th octave (~F4), although what caused my 
to shift down to the 5th partial then, was not so much that I could 
find the 7th, but that it decayed to quickly. By the 5th octave, I'd 
already shifted down to the 3d partial, while still using this 
principle of zero-beating the highest audible partial.

At 4:54 PM -0400 10/23/04, Don wrote:
>The aural results are what matter,
>and those, to my ear, were unacceptable.

Unless you can be specific about why these aural results were 
unacceptable to your ears, we'll have to wait to get to a piano. In 
the meantime, thanks for your ideas.