Robert Conrad, Registered Piano Tuner/Technician, Tucson, AZ

Lowering the FAC Tenor Partial Change: The “How”

Start by setting the SAT’s ‘Up or Down Memory Storage’ to DOWN.

The STO/MEM + Note UP or DOWN command sets the direction the SAT will automatically go, after a note is stored.

When the SAT is first turned on, storing a note setting will automatically increment the note setting to the next higher semitone.  But automatically stepping up to the next higher semitone is not convenient when tuning and storing the bass notes.

To change the storage direction, hold down the MEM button and then press the NOTE DOWN button, release MEM and then release the NOTE DOWN (or UP) button.

The SAT IV’s display will show ‘Store down’ (or ‘Store up’) as long as the MEM buttons are pressed.

{To get back to the normal or the default ‘UP’ direction, repeat the procedure using the NOTE UP button instead of the NOTE DOWN button.   Turning the SAT OFF will also reset the direction of the note storing back to its default ‘up’ direction.}

To lower the partial change:

Here is a video of the routine:

As usual, measure and store an FAC tuning to a page of memory.

Look at the cents difference between notes C3 and C#3 on the FAC tuning.
(It will probably be .3 c.,  or .4 c.,  or .5 c. &c.).

That same cents difference will be used for lowering the partial change.
Lets say the difference between C3 and C#3 is .5 cents.

With the SAT on the page with the FAC tuning, set the SAT to C3.
Lets say the setting on C3 is (C3 @ -2.5)

Press tune and the SAT should say (C5 @ -2.5).

With the Note Storage setting set to Store Down,
p
ress Blue Shift +  STO/MEM and (re)store the setting for C3.
(This re-storing of C3 sets the SAT to the correct partials).
The SAT should show (B2 @ -2.5).  (But it is using the correct 4th partial)

Change the cents by the amount of the cents difference (found between C3 and C#3).
i.e. (B2 @ -3.0)

Press Blue Shift and then STO/MEM to store the setting.
The SAT should now show (A#2 @ -3.0).

Change the cents by the amount of the cents difference (found between C3 and C#3).
(A#2 @ -3.5)

Press Blue Shift and then press STO/MEM to store the setting.
The SAT should now show (A2 @ -3.5)

Change that cents setting to -4.0 (A2 @ -4.0) and press Blue Shift + STO/MEM
The SAT should now show (G#2 @ -4.0).

That’s it.  You’re done.

Press MEM to put the SAT back onto the FAC tuning.

The FAC tuning in your SAT now uses the 4th partials from A2 – A4 for a complete Two Octave Temperament range.

To check your work, press the MEM button and use the Note Up/Down buttons to scroll through those notes around G2 – C3.  You should see the numbers make a cents ‘jump’ between G#2 and A2.

 

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