post pitch-raise creep?

[J Patrick Draine]

On 7/7/06, ReggaePass at aol.com <ReggaePass at aol.com> wrote:
>
> What do fellow listers experience as the average amount of time a piano needs to settle from a pitch raise before it is ready for a fine tuning from 20 cents?  50 cents? 100 cents?
>

While you may well get a great variety of individuals' unique
perspective on "time needed to settle", I believe some years ago Dr.
Albert Sanderson utilized the much maligned "scientific method" (and
volunteer labor in the form of NBSS students eager to do yet another
practice tuning, yea even a pitch raise or lowering) to study these
questions. His initial one-size-fits-all overpass percentage was 25%
in the early models (I & II) of the SAT, although even then he
acknowledged that less was optimal in the bass, and more as
appropriate in certain sections of the tenor and treble (especially if
one strip mutes and pulls the unisons in after tuning all the unmuted
strings).
His studies did finds that the "settling" was immediate and proceeding
to the fine tuning right after the pitch raise was optimal (especially
for the customer, rather than having to endure listening to an
extremely rough tuning for some days or weeks until the followup
appointment resolved the problem. And of course they won't be needing
to pay for your extra drive time etc.). With the greater percentage
that the piano is flat, more passes in that session are indeed
necessary.
On the other hand --  if the instrument is expected to have critical
use (performance, recording, practice sessions by professional
musicians) -- a followup is indeed imperative (as well as a climate
control system in the piano) even if the pitch correction had been a
mere 10 cents (just one bad unison and the artist, the hall, and
especially the technician look really really bad).
Patrick Draine