pitch

[Denis Brassard]

Greg,
If you are familiar with logarithms, there is a simple formula you can use
that works for every frequencies on any given note at the piano.
Here it is:

1+ Log (Freq./27.5)/ Log (2) X 12 = Note Number

In your post you mentioned 435 Hz.

1+ Log (435/27.5)/ Log (2) X 12  = 48.8021

48 is your note number, i.e. G#4 and the decimal part X 100 is the amount
that note is sharp; i.e. 80.21 cents.
A semitone being 100 cents, G#4 +80.21cts = A4 -19.79cts.
When you stated A 435 being offset by 19.79 cents, you were right on the money.

Regards,

Denis Brassard,
Head Piano Technician
SUNY Potsdam
Potsdam, New York.


>Hi Greg,
>
>Each beat per second is roughly equal to 4 cents. Hence, 440 bps -
>435 bps = 5 bps X 4 cents = 20 cents. Your offset was pretty close,
>I'd say.
>
>Best wishes,
>
>Tom
>
>>Greetings folks,
>>    I recently tried to tune an older instrument that seemed as though
>>it was designed for 435. I went about it in an unusual way. Since I'm
>>just dense enough not to remember the formula I had to figure out how to
>>offset the ETD to read for 435. In TuneLab (check out the new TuneLab
>>PRO) I used the mouse on the left side of the floating boxes window
>>until the frequency said 435. When I did that the offset read -19.79.
>>Does this sound correct to you folks or did I mess up again?
>>    o.k. that's one more item off of my to do
>>list............................
>>
>>--
>>Greg Newell
>>Greg's Piano Forté
>>12970 Harlon Ave.
>>Lakewood, Ohio 44107
>>216-226-3791
>>mailto:gnewell@ameritech.net
>
>
>Tom Seay
>Piano Tech Office
>School of Music
>The University of Texas at Austin
>(512) 232-2072
>mailto:t.seay@mail.utexas.edu