[pianotech] offset of SAT to non-440

[David Ilvedson]

Here's what I do.   I have my FAC numbers written on the plate or hammers in pencil (I recheck on occasion and make changes as needed) I enter my FAC numbers and store on a page.   I then go through checking all the A's to see what is going with the pitch in general.   I make a guess about how flat or sharp the piano is overall.   Shut off the machine, restart and off set the pitch.   Then open the page of that piano and recheck the A's.   Because pitch is never exactly 5 cents sharp on every note, in the deliberations I may decide not to bring the bass up to match the sharp tenor.   I may bring the bass up a little and the tenor down a little...compromising...

I have not tried off-setting as you wrote...if I'm on a new piano/customer.   I always just bring the string up to pitch for the FAC readings...

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "David Nereson" <da88ve at gmail.com>
To: pianotech at ptg.org
Received: 8/3/2009 1:41:30 PM
Subject: [pianotech] offset of SAT to non-440


>    First of all, I did call Inventronics about this first, but 
>just couldn't seem to get "on the same page."
>    This time of year, most pianos are sharp from summer 
>humidity.  Rather than lower them all down to A440, knowing 
>they'll need a pitch raise in November if I do, I just tune them 
>sharp.  This requires offsetting the SAT to a sharper pitch.
>    Following the outlined procedure in the instruction manual, 
>I turn the unit on, press Tune, then play A4 on the piano, then 
>press the Cents Up button on the SAT (III) until the lights 
>stop, then press Shift, Reset.  The unit should now be offset to 
>the higher pitch.  Then I go ahead and measure the SAT numbers 
>and store them to a page in memory.  Before starting in to tune, 
>I go to A4 on the SAT and play A4 on the piano to make sure the 
>lights are still stopped, i.e., that the unit is offset to the 
>pitch of A4.
>    Here's the problem:  the lights are never stopped at A4 
>after performing the offset. They're always rotating 
>counterclockwise, indicating that A4 is flat!  Well, I don't 
>want to raise the piano any sharper!  Why, after having 
>supposedly offset the unit's reference point, does it still show 
>A4 as flat?  Should I have A5 or A6 in the window when I offset? 
>(I've tried both, and it doesn't seem to make any difference.) 
>The guy at Inventronics said to "drop down a couple cents," or 
>to "leave off a couple cents" or something like that, but I'm 
>not sure what he meant.
>    In reality, I don't raise the whole piano to the sharpness 
>of the low tenor, which is usually the sharpest area of the 
>piano.  I'll lower the low tenor some, leave the treble where it 
>is, and maybe pull the bass up a tad.  On older pianos, I don't 
>like to have to pull the bass up ANY, because of possible string 
>breakage, but if I don't then I have to lower all of the tenor 
>and treble, and do a pitch raise when November comes along.  And 
>these school systems don't want to tune more than once a year if 
>they can get away with it.
>    But I digressed.  Why don't the lights stand still after 
>having supposedly offset the pitch?
>    --David Nereson, RPT
>