Richard, One equation used to find the frequency of a note is the following: (1.a) 2^((N-1)/12) * 27.5 where N is the note number. 2^((49-1)/12)* 27.5 = 440 hz ... for A4 I took the next 2 formulas from Dr. Albert Sanderson: (1.b) I=Bn^2 B is the inharmonicity constant and n is the partial number. B can be calculated as follows: (1.c) B= (330*d)^4/(T*(L^2)) diameter and length are in inches, tension is in pounds. Let us suppose that this note has an Inharmonicity constant (B) of .9 cents. I= .9 * (1^2) or .9 cent for the first partial. Its frequency is: (1.d) 2^(((N-1+(I/100))/12)*27.5= frequency 2^(((49-1+(.9/100))/12)*27.5 = 440.229 hz To find the frequency of all the partials on that note use: (1.e) 2^(((N-1+(I/100))/12)*27.5 * n For example,the frequency of the 4th partial of note 49 will then be this: I= .9 * (4^2) or 14.4 cents and 2^(((49-1+(14.4/100))/12)*27.5 * 4 or 1774.7 hz I hope this helps. Denis -----Original Message----- From: Richard West [mailto:rwest1@unl.edu] Sent: Monday, February 11, 2002 8:52 AM To: College & University Technicians Subject: frequencies Hi, Everyone, Is there anyone out there who has the formula for calculating the frequencies of the partials of a string in a piano taking into account the inharmonicity of the string? A-440, for example--the actual frequency of the second partial must be 880.??? or 881.??? At this point I'm only interested in the plain wire strings. I know bass string formulas get to be pretty complex. Richard West
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