Subject: SV: bite bar and bone conduction From: Stefan Stenfelt <stefan.stenfelt@xxxxxxxx> Date: Fri, 14 Sep 2007 10:21:58 +0200 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Christian, I did an experiment looking at sensitivity stimulating by bone conduction via the teeth. There is also a JASA publication on transmission of BC sound via the teeth. In my investigation we found the sensitivity for stimulating at the teeth to be similar to that exciting BC at the skin covered mastoid. However, the sensitivity depends on the mass of the bite bar, i.e. a heavier bite bar yields lower sensitivity at the high frequencies (acting as a low-pass filter). Although not investigated explicitly, we did not se any variation of the sensitivity with bite pressure. However, the measurement time was important since the subjects fatigued after some time and it was difficult to maintain enough bite pressure. Look at Stenfelt and Håkansson, Scand Audiol, 1999, 28(3):190-8 Dahlin et al, JASA, 1973, 53:1434-7 //Stefan Stefan Stenfelt, Technical Audiologi,+46 13 222856 -----Ursprungligt meddelande----- Från: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxx För Christian Kaernbach Skickat: den 13 september 2007 22:26 Till: AUDITORY@xxxxxxxx Ämne: bite bar and bone conduction Dear List, We plan to do experiments involving bite bars and bone conduction. We could use normal bone conduction transducers strapped to the mastoid but it might be compelling to apply the sound via the bite bar. Has anybody experience with sound application through bite bars? I have found in the internet that potential users of BAHA (bone anchored hearing aids) are encouraged to test the effect of bone conduction sound via bite bars. It could be that bite bar sound transmission will be variable depending on bite pressure. We will use bite bars with dental impressions. Hopefully these will ensure a good contact so that sound transmission should not depend too much on bite pressure. A five-dB variability would be acceptable. ... And what about the sound transmission to the table? Can it be ignored? Would mounting the bite bar to the table make it more difficult to apply sounds via the bite bar? Thanks in advance, Christian -- Prof. Dr. Christian Kaernbach Allgemeine Psychologie Institut für Psychologie Christian-Albrechts-Universität zu Kiel Olshausenstr. 62 D-24098 Kiel Germany www.kaernbach.de