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Re: Origin of the Mel frequency scale equation?



Rachel, thanks for those sources. I had a bit of trouble finding the 1965 one until I realized the name is spelled Pedersen.
http://links.jstor.org/sici?sici=0022-2909(196524)9%3A2%3C295%3ATMS%3E2.0.CO%3B2-5


A related nonlinear frequency scale is Don Greenwood's place map. In 1947, Stevens essentially claimed that the mel scale is a place map: "it has been found most convenient to analyze speech by dividing it up into bands that stimulate equally wide regions on the basilar membrane. This is accomplished by choosing filter cut-offs at equal intervals along the mel scale of subjective pitch" ( The Journal of the Acoustical Society of America -- September 1947 -- Volume 19, Issue 5, pp. 771-780, S. S. Stevens, J. P. Egan, and G. A. Miller "Methods of Measuring Speech Spectra"). But I don't think he showed that his pitch magnitude method was actually related to a cochlear place map. Greenwood came at it from animal CF data, if I recall correctly, and came up with somewhat different formulas. I have his papers in my office and can comment more after I get home and look at them; here's a plot: http://books.google.com/books?id=q1hoIKeBi90C&pg=PA135&dq=greenwood+place+map+frequency&lr=&as_brr=0&ei=_WPaR6nDEYHwjAHGx6XUBg&sig=AyneJQnz8PSYMRYpdUfItampmgs

Dick

At 9:58 AM +0000 3/11/08, Rachel van Besouw wrote:
Apologies, in chronological order that should have been:

Pederson (1965), Fant (1973) and then O'Shaughnessy (1978) !

:-)

\Rachel