[pianotech] A440 Tuning Fork

[Ron Nossaman]

Good grief, people. Years ago, Jim Coleman posted the math, and it's 
been reposted many times since as formulas, and in spreadsheets. Did 
anyone bother to save any of it?

pitch deviation = starting pitch*2^(cents deviation/1200)
So 440+10¢ = 442.549

cents deviation = 1200*LN(Hz/target Hz)/LN(2)
So 440-3Hz = -11.44¢

Ron N