From what I've read the Persian Santur is usually tuned to the Phyrgian mode, but what are the actual frequencies or ratios of the notes? How would I tune one by ear? e.g. a piano tuner might count beats.
I have found little information in English, but one video (How To Tune A Persian Santoor) shows:
D♯ 158.2 Hz +28 cents
F 349.2 Hz +0 cents / 176.9 Hz +22 cents
G 784.1 Hz +0 cents
A 438.7 Hz -5 cents
A♯ 465.8 Hz -1 cents / 233.6 Hz +4 cents
C 523.4 Hz +0 cents / 262.2 Hz +4 cents
D 587.0 Hz +0 cents / 146.6 Hz -2 cents
If we take just the cent values we can guess at the following ratios:
D 0 cents 1/1
E♭ 129 cents probably 27/25, 133 cents
F 301-323 cents 6/5
G 501 cents probably 4/3, 498 cents
A 696 cents probably 3/2, 702 cents
B♭ 800-805 cents probably 8/5, 814 cents
C 1001-1005 cents could be 16/9 996 cents, or 9/5 1018 cents
Am I close here? What are the most commonly used ratios? Is there some intentional tempering? Is it different for e.g. Persian vs Indian music?
In an interview with Sourena Sefati he mentioned using quarter tones and I have heard this mentioned by Indian musicians as well. But I thought quarter tones would normally refer to 24-TET not pure intonation, so this adds to my confusion.