Subject: From: "Richard F. Lyon" <DickLyon@xxxxxxxx> Date: Sat, 8 Dec 2007 11:03:26 -0800 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>The "second filter" is an obsolete concept that was caused by misunderstanding the relationship between broad filters and sharp iso-response tuning curves in a compressive nonlinear system. See my paper AUTOMATIC GAIN CONTROL IN COCHLEAR MECHANICS http://dicklyon.com/tech/Hearing/AGC_MOH1990-Lyon.pdf or video of my recent cochlea modeling retrospective talk: http://www.archive.org/details/Helen_Wills_2007_10_01_Richard_Lyon Dick At 11:06 PM +0530 12/8/07, vishal kooknoor wrote: > Please can anyone provide me information about the "second >filter" which is hypothesized to be in between the "first filter" of >basilar membrane and auditory nerve fibers.