Pitch Raise, was: Standard Pitch

[cswearingen@daigger.com]

Ed,

When you say you like "a very tight topstring for stability" is this the
same thing as saying you like to place the non-speaking length at a
slightly greater tension than the non speaking length?  Further, does this
suggest that bringing the string down to pitch can make the note less
stable than bringing it up to pitch?

Thanks,
Corte Swearingen
Chicago


                                                                                                         
                      A440A@aol.com                                                                      
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                      @ptg.org                 Subject:  Re: Pitch Raise, was: Standard Pitch            
                                                                                                         
                                                                                                         
                      10/10/2003 01:52                                                                   
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Corte writes:

<< as I understand it, whichever direction
you move the pitch, it tends to want to spring back by about a third.  So,
in general, you move the pitch 3 cents in one direction, it will settle
about 1 cent back in the other direction.  This is the whole basis of
overshooting the pitch during pitch raising.<<

     I think the Sanderson number is 25%.  I have found SAT raises to often

be dead on when I begin to tune after the raise. One thing I do that I
haven't
seen proposed is that I take my readings an octave above where I am, ie,
right
above the bass break is usually way sharper or flatter than the rest of the

piano, so I don't set the SAT correction there, I go up about an octave and

measure. Then I go back to the break note and bring them up.  When I have
traveled up an octave, I measure another octave above etc.   It isn't
uncommon to do
a 15 cent raise and find that many of the notes are within 2 cents of final

when I begin the tuning.

>>Now, if you are fine tuning and you pull the pitch up to 6 cents and then
move it down to the target pitch, it will end up creeping back up by a
couple of cents.  In other words, in my opinion, you're not fine tuning if
you're moving pitches around by 5 or 6 cents as you describe below.  <<

   I haven't found that to be true.  I don't see strings creeping back up
after I place them.  On a tight pinblock, I am often moving the string down
below
pitch and letting the pin's release pull them back up to almost on target.

Then a very light wiggle of the hammer upward and the pitch is set.
    I like a very tight topstring for stability, but most final tuning is
done with pin flex.  I am very aware of the torque and bend of the tuning
pins as
I go through a piano, and a number of the pianos in my clientele are tuned
100 times a year.  The use of pin flex doesn't necessarily damage the pin
or
block.(in fact, you can't turn a pin with 120 lbs of torque without flexing
it).

Regards,
Ed Foote RPT
www.uk-piano.org/edfoote/
www.uk-piano.org/edfoote/well_tempered_piano.html
 <A HREF="http://artists.mp3s.com/artists/399/six_degrees_of_tonality.html
">
MP3.com: Six Degrees of Tonality</A>
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