stretching

[ATodd@UH.EDU]

   I have been asked about the stretching process by a teacher on the piano
list. I answered as best I could, but am wondering if someone out there
could answer better, bearing in mind this is a non-technician. Here is the post.
RE: I have recently had firsthand exposure to a tuning technique (method, style?--I
don't know what to call it) that "stretches" the intervals in the upper range of
the piano.  This is supposedly done in such a way that the piano is still "in
tune."  It has the very pronounced effect (in the pianos that I have heard) of
brightening the upper register considerably.  On some pianos this effect is very
dramatic--it sounds like the piano has been voiced up in that register.
However, in some instruments it seems to have the effect of creating (to my ear,
at least) certain "wild" tones (again, my vocabulary does not suffice), that is,
notes that I can't confidently call out of tune, but which nonetheless have a
grating or at least non-uniform tone quality to them.  This is something that is
definitely independent of voicing.
My questions are:

1) is this a common and accepted tuning practice?

2) are there accepted pros and/or cons to this manner of tuning?

3) and, more generally, are well-trained tuners expected to be able to employ a
variety of tuning techniques (methods, styles--those terms again!) to suit the
ears of an individual player?

Thanks in advance for your response!

ALSO:
   his tuning sounds somewhat
strange to some of us.  It's hard to pin down, especially since none of us on
the piano faculty can really pinpoint what the issue is.  I'm not sure even
where I stand.  I was thrilled when my tiny Steinway S suddenly had a brilliant
upper register after a mere tuning.  It was really astonishing.  But not all
pianos seem to respond as well.  I'm just curious to know if there is some kind
of consensus and or established debate in the technician's community regarding
this.

****************

   I hope this subject hasn't been beaten to death before I got on the list.
If so, I will understand. But if anyone would like to comment on his questions,
I'll be glad to forward your comments.
   Thanks again for your help.

Avery Todd, RPT
University of Houston
atodd@uh.edu

P.S. Comment privately if you prefer.