Tips For SAT Users

[Richard Raskob]

Hi Jim!

    I have a method similar to Kevin's to adjust the width of the octaves
with the SAT III.  After taking the FAC readings I tune F#4 very carefully.
I then set the SAT III on B2.  I play F#4 and use the double octave
adjustment to stop the LED's .  I found that setting the A3 - A4 octave to
my liking sometimes did not make a B2 -B3 octave that worked!  Using this
method I find that the whole C3-C5 section sounds very nice!

Richard Raskob RPT

PS  I have also figured out a way to have the SAT II perform a similar
result but it is much more complicated.  I am willing to post the steps if
there is interest.  The D.O. adjustment that the SAT III has makes the
upgrade worthwhile all by itself!
----- Original Message -----
From: "Jim Coleman, Sr." <pianotoo@imap2.asu.edu>
To: <pianotech@ptg.org>
Sent: Thursday, November 30, 2000 8:21 PM
Subject: Tips For SAT Users


> Special help for SAT users
>
> The newer Sanderson AccuTuners (SAT for short) have the (FAC)
> capability for predicting or calculating a tuning for a piano.
> Although the measurements of F3, A4 and C6 will provide
> a very good tuning for most all pianos, one may alter this
> tuning to suit one's personal preferences. For example some
> Technicians prefer to have their octaves very tight while others
> prefer to have a little stretch in the octaves. Measuring the
> 3 notes gives the instrument a pretty good idea of the slope of
> the inharmonicity of the piano, but it does not tell everything
> about the bridge shape or where the string sizes or type change.
> Originally there was a program for measuring 6 C's of a piano
> to predict the tuning, but here again, wire size changes and
> bridge configurations were not known to the program. One could
> measure the inharmonicity of every note on the piano, but this
> would be tedious and impractical to do for each tuning job. As
> a result Dr Sanderson came up with the scheme to measure only
> 3 notes to still get a pretty good representation of the tuning
> requirements for a particular piano.
>
> If a treble bridge has a hockey-stick like bend at the bottom
> It is likely that some additional stretching could be advantageous
> for the tuning of this piano. I am indebted to Kevin Ramsey
> for this simple way of determining if additional stretch should
> be welcomed. Here is his procedure:
>
> After measuring and computing a tuning for a piano using the
> FAC capability, carefully tune the A4 to the SAT. Then press
> Dn/OCT to A3, play the A4 again and notice the direction of the
> LED's. If they are stationary, you would have a tight 4-2 type
> octave when the A3 would be tuned to this setting. This means
> that the second partial of A4 is exactly in tune with where the
> 4th partial of A3 will be when it is tuned later. This is quite
> understandable when you realize that the SAT (FAC) tunings tune
> by the 4th partials of each note from C3 through B4. When the A4
> is played while the SAT is on A3, it is the 2nd partial of A4
> which is being viewed on the display. When the display is set
> this way for the tuning of A3 later, its 4th partial will be
> tuned to this setting. In essence you will have a perfect unison
> between the 2nd partial of A4 and the 4th partial of A3. This
> would give you an aural test where the M3rd F3-A3 would beat at
> the exact same speed as the F3-A4 M10th.
>
> If on the other hand the LED's are rotating counterclockwise in
> the above example, the octave would be narrow when the A3 is
> later tuned to the A3 setting. This would result in an aural
> test where the M3rd would be faster than the M10th. This would
> indicate that we would need to stretch the tuning more.
>
> Additional stretching can be done in two ways. For those who
> have the SAT III, the blue SHIFT button is depressed while the
> Up/CENTS button is pressed 2 or 3 times to stretch the tuning
> by .3 beats per second (bps). This will give the A3 a lower
> cents setting while the A4 setting will remain the same. In
> most cases this will at least make the 3rd-10th tests equal
> or better. On some pianos one might wish to add a little more
> stretch by increasing the Double Octave Beat control (DOb) to
> .5 bps.
>
> For those who have the older SAT II or SAT I with the FAC
> capability, they can increase the value of the A4 Stretch
> number by perhaps .5 to .7 cents to accomplish the same thing.
> However it is important to remember when you get up to C5 in
> the tuning process that it is necessary to add the same amount
> to a reset of the instrument's pitch by using the SHIFT and
> RESet buttons. Two articles in the PT Journal of Apr and May
> in 1997 explain this in greater detail.
>
> It has been noted for several years that the better tuners
> prefer to stretch their octaves at least to show a half bps
> difference between the M3rd F3-A3 and the M10th F3-A4 with
> the 10th being the faster. This can be easily duplicated
> using the SATs.
>
> For those still using the older single F4 Stretch number
> system Rick Baldassin wrote an excellent piece on doing a
> similar thing for the SOTs and the early SAT's. In this case
> the reset additions need to be made between F4 and F#4.
> If there is enough interest, it might be possible to get him
> to repeat that for us here on pianotech.
>
> Jim Coleman, Sr.