[pianotech] Stretch in tuning

[Ron Nossaman]

On 5/25/2012 7:01 PM, David Lawson wrote:
> This is a subject that has haunted me for ever. We all know that piano
> tuning is subjected to all sorts of rights and wrongs, as there are so
> many opinions out there. The stretching of octaves is,(as you say),
> during get togethers, mentioned in passing, and then dropped.

This confused me for some time. Didn't the inharmonicity of piano 
strings guarantee a pure sounding octave was stretched? One out of state 
expert who came in to replace a set of hammers on one of the 
university's Steinways (gotta have a Steinway expert, you know) even 
carefully explained to me how he "started stretching" octaves at the 
beginning of the capo section, and went up to about eight beats per 
second in the octave at c-7/8! I heard that tuning, and wasn't awfully 
convinced, nor was I awfully convinced by the tunings I followed that 
were flat through octave 5-6, and were nearly a semitone sharp at c-8. I 
never had anything resembling decent tuning instruction, so it took me 
some time to piece a sensible picture together from what I heard from 
others, read, and found in others' tunings. Learning something about 
more meaningful interval tests (piecemeal) from better educated aural 
tuners finally cleared up a lot of misinformation and the process became 
a lot more sensible to me. The closer I get to understanding how all 
this works, however, the more I realize that pianos aren't entirely tunabe.
Ron N