Subject: Auditory place maps From: Jont Allen <jontalle@xxxxxxxx> Date: Sat, 15 Mar 2008 22:29:14 -0400 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Re the below comment from Dick Lyon: The history of cochlear place-maps goes back at least to Steinberg in the 1930's, and maybe before. The work of Greenwood then followed that of Fletcher and integrating the Frequency JND, which Fletcher showed was closely related to the critical band. See page 1836 for the formula for the critical band, derived from the critical bandwidth and the width of the BM. In my view, Steven's doesnt get any credit at all here, given this very long and well documented history of the cochlear map. My comments are based on a detailed analysis of Fletcher's work, part of which is summarized in an invited review paper that was published in JASA: title: Harvey Fletcher's role in the creation of communications acoustics journal: JASA year: 1996 volume:99 pages: 1825--1839 If your interested, I have written other papers on this topic as well. Jont Date: Fri, 14 Mar 2008 04:59:28 -0700 From: "Richard F. Lyon" <DickLyon@xxxxxxxx> Subject: 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 Date: Fri, 14 Mar 2008 04:59:28 -0700 From: "Richard F. Lyon" <DickLyon@xxxxxxxx> Subject: 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 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