Mapping A0 can be done any number of ways.
A0 can be mapped however you like, but once you have it where you want it, it’s location must be measured using it’s 4th partial. The LC Spreadsheet uses the 4th partials for A0 – A4 for creating the tuning.
If you want to tune A0 aurally, fine, just make sure when you’re done, you measure A0’s location using its 4th partial.
To measure A0 using its 4th Partial:
1. In the TUNE mode, set the SAT to (A2 @ x.x)
2. Play A0 and stop the lights using the cents buttons.
The number in the SAT’s display will be the location of A0 when measured using it’s 4th Partial.
Some technicians use the 6th partials, or the 8th partials, or whatever, to tune A0. Again, that doesn’t matter. Find A0’s best location however you like, but just make sure when you’re done, you measure A0’s location using its 4th partial.
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I have always liked using the 5th to help me find a good position for A0. So I wanted to find a way to use E1 to help me find A0.
E1 must be tuned in some way, so it can be used as a reference note. This preliminary tuning of E1 is not an exact or ending placement tuning, it is just tuned in such a way so it can be used used as an approximate reference note.
Tuning E1 from A1 is the interval of a 4th. But that low in the piano, tuning a 4:3 4th is not much help.
But tuning an 8:6 “4th”, it is very usable.
To find a reference note location for E1, tune the E1/A1 8:6 4th, 4 cents wide.
1. Set the SAT to (E4 @ x.x) play A1 and stop the lights (in TUNE mode of course).
2. Once the lights are stopped, subtract 4.0 c. from display setting, and then tune E1 to that setting.
E1 is now tuned close enough for it to be used as a reference note for tuning A0.
Tuning A0 from E1:
Just like trying to use a 4:3 4th for tuning E1, trying to use a 3:2 5th in this part of the piano won’t work very well either.
Instead of using E2 and the 3:2, set the SAT to E3 (as the coincident partial), and use the 6:4 ‘5th’ for tuning A0.
Tune this E1/A0 6:4 5th, 5.0 cents wide.
1. In TUNE mode, set the SAT to (E3 @ x.x), play E1 and stop the lights.
2. Subtract 5.0 c. from the SAT’s display setting.
3. Tune A0 to that setting.
Now listen to this location using whatever checks you like.
Once happy with the location of A0, measure it’s location using it’s 4th partial.
To do that, set the SAT to (A2 @ x,x), play A0, and stop the lights.
The cents setting in the SAT’s display is the 4th partial location number needed by the LC spreadsheet to create the tuning.
Make sure you write down this A0 number.