stability of pitch raises

[Paul Tizzard]

Hi list

I also thought I had seen something Al Sanderson had written about starting
a pitch raise from A0, and continuing onward and upward chromatically. I had
always started pitch raise's with setting a temperament, and tuning as per
normal as quickly as possible. Obviously the only way to do the chromatic
pitch raise is with an ETD. Can anyone expand on the chromatic technique?

If one starts at A0, you're adding whatever extra "tension" there
would be that occurs from a pitch raise, to the "middle" of the soundboard
first? If I'm correct in assuming that, would that have any effect on the
outcome of the tuning? Also, one is adding tension to the frame in a
different sequence to the way you would starting with the temperament. This
should also have an effect?

I mentioned this to an RPT ( the only one in the area ), and he said he
hadn't heard of doing a pitch raise like this, which made me think I had
misunderstood what I had read.

Any comments would be appreciated.

Paul Tizzard, Piano Tuner
Cape Town
South Africa

----- Original Message -----
From: "Z! Reinhardt" <diskladame@provide.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Friday, August 31, 2001 12:22 AM
Subject: Re: stability of pitch raises


> One person you might want to talk to is Doc Sanderson (Dr SAT himself) at
> Inventronics.  He has done research on the effects of doing a pitch raise
> "piecemeal" (start with a temperament, tune single strings, then pull in
> unisons) versus "brute force" (crank all pins from one end of the piano to
> the other).  If I remember correctly, he has found that the "brute force"
> method [my terminology] results in more stable tuning at pitch using a
> smaller overpull than would be necessary to do a "piecemeal" pitch raise.
> He may have an explanation for this phenomenon.