A Multiplier Default
In SAT IV, the default “A” Multiplier for FAC tuning is 1.0. You can change this value through the SAT IV MENU feature.
Recommended Setting for A440
To place A4 closer to the A440 standard, set the A Multiplier Default to 0.8. Without this adjustment, FAC tunings often place A4 slightly sharp. The amount varies by piano, but it is typically about 1.0 to 1.5 cents sharp.
Earlier Manual Method
Before the SAT IV MENU allowed users to change the A Multiplier Default directly, Jim Coleman Sr. used a simple manual method: he multiplied the measured FAC “A” number by 0.8 before entering it. This narrowed the midrange stretch slightly and brought A4 much closer to A440.
For example, if the measured FAC “A” number is 10, enter 8 instead. This approach produces an A4 setting very close to A440 and can also be used with older Accu-Tuner models.
Current SAT IV Practice
Because this adjustment proved reliable, it was added to the SAT IV MENU system. SAT IV users should set the A Multiplier Default to 0.8 rather than 1.0. This setting improves A4 accuracy and helps FAC tunings align more closely with the A440 standard.