Robert Conrad, Registered Piano Tuner/Technician, Tucson, AZ
Correcting Partial Changes in FAC Computer-Generated Tunings Using the Sanderson Accu-Tuner IV Overview of Partial Changes in FAC (Computer-Generated) Tunings All ‘computer generated’ tunings include partial changes, and these partial changes may sometimes contain errors. By correcting these errors, the overall sound quality of the tuning can be significantly improved. The number of partial changes…
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. Press BluShift and then STO/MEM to store the settings for B2, A#2, and A2. (Contains button pressing video).
When using the A2-A4 range for tuning a 2-Octave Temperament, all the notes within that 2 octave range need to use their 4th partials. This eliminates any possibility of a partial change error in that A2-A4 range. (Contains button pressing video).
The need for this tweak has been around for some years now, but it should be used whenever using an FAC tuning. (Contains button pressing video).
We need to know exactly where the 4th P of A4 is so we can be sure the FAC tuning is tuning A4 to @ A440.
There are a number of ways, when using an AccuTuner, to tune to non standard pitch. PCC is one of the easiest and most versatile. When PCC is used for tuning to non standard pitch, make note of the PCC adjustment so it can be reversed when the tuning is finished.
Using a sequence is a great way to quickly tune and make aural checks before committing to the complete tuning. (Contains button pressing video).
All computerized tunings have partial changes and those partial changes may contain an error. Correcting these errors can improve the sound of the tuning. This procedure will show how to correct the three FAC partial changes when using an AccuTuner SAT IV. But before correcting the partial changes, consider lowering the tenor partial change from…
This Partial Change Correction (PCC) feature is relatively new to the SAT IV’s programming. So if your SAT doesn’t seem to be responding to the STO + MSR command it’s program may need to be updated. Being able to correct partial changes is unique to the AccuTuner. An FAC tuning has fewer partial changes (3) than any other tuning system, and yet it is the only device capable of correcting them. (Contains button pressing video).
This post is part of a series on working with an FAC tuning. There are a number of tweaks that can be done to further fit an FAC tuning to the piano, before changing the F number.
Programming a custom over pull is so easy it’s not worth making a video of it. The custom over pull is ‘activated’ just like the regular pitch raise feature, but instead of rolling off onto the BlueShift, after MSR stops the lights, roll off onto the Green Shift. Rolling off on to the GREEN shift activates he Custom Over Pull and uses the amounts stored on Page 123.
DOB allows us to easily stretch or contract a template or tuning stored in the SAT.
Tweaking the treble stretch in an FAC tuning is a great way to ‘customize’ a tuning.