Subject: formant filtering From: REDDY SIVAPRASAD <rsivaprasad(at)HOTMAIL.COM> Date: Tue, 4 Mar 2003 08:33:30 +0530Dear Mr. Blumschein and colleagues, The idea of formant filtering studies is that the formant amplitude (peak to trough) will be more in case of 'clear speech'. So, the filtering or restricting the formant band width will serve the same purpose. Studies in this area have been started with this idea. No doubt its really interesting to see possible physiological mechanisms at the level of VIII nerve and above. Good review of effects this method and other methods to simulate clear speech is available in: Revoile, S. G., & Holden-Pitt, L. D. (1993). Some acoustic enhancements of speech and their effect on consonant identification by the hearing impaired in Studebaker and Hockberg (Eds). Acoustical factors affecting hearing aid performance. Allyn and Bacon : London. I would also like to mention to the list that one major hearing aid manufacturer has introduced this algorithm in his latest and flagship products. I have some personal experience that some hearing impaired experienced listeners have definitely felt the difference. I would like to listen your opinions on this. Thanking you, M. Reddy Sivaprasad Junior Research Fellow, Dept. of Audiology, AIISH, MYSORE-6 Karnataka India Ph: +91-821-514449 Fax: +91-821-510515 _________________________________________________________________ Cricket World Cup 2003- News, Views and Match Reports. http://server1.msn.co.in/msnspecials/worldcup03/