Re: Critical bands v hearing loss (beaucham )


Subject: Re: Critical bands v hearing loss
From:    beaucham  <beaucham(at)MANFRED.MUSIC.UIUC.EDU>
Date:    Tue, 27 Sep 2005 09:16:22 -0500

Dear List, I'm not sure about the hearing-aid case, but in the case of normal listening, this is a personal interest of mine. I have been interested in spectral data reduction for the dual purpose of better understanding musical timbre and for developing better methods of musical sound synthesis. Last spring a colleague and I did an experiment on critical band data reduction of some musical tones, and I gave a paper on it at the spring ASA meeting: Beauchamp, J. W. and Horner, A. B. (2005). "Effect of critical- band smoothing of musical instrument spectral data" (A), J. Acoust. Soc. Am. 117 (4), Pt. 2, 2476. Two methods were used: 1) replacing the spectra within critical bands by static spectra with common amplitude and frequency controls; 2) smoothing instantaneous spectra with critical band filters. The Zwicker/Terhardt critical band formula (JASA, Nov., 1980) was used, but for both cases we employed a bandwidth multiplier in order to get a discrimination-vs.-multiplier psychometric curve. The preliminary results showed that at least for "young acute normal" ears, you need bands narrower than critical band in many cases, particularly for low piano tones. Nevertheless, from casual listening it appears that CB data reduction may be acceptable in many cases, e.g., in comparison to MP3 data reduction. Jim Beauchamp Univ. of Illinois at Urbana-Champaign >From: Vinay SN <vinaysn(at)LYCOS.COM> >Date: Thu, 22 Sep 2005 01:04:59 -0500 >To: AUDITORY(at)LISTS.MCGILL.CA >Subject: Re: Critical bands v hearing loss >Comments: To: "Richard H." <auditory(at)AUGMENTICS.COM> > >Dear list, > >The human ear can only make sense of one signal per critical band. For >example, if two sine tones of 100Hz and 110Hz are played, two distinct >tones are not heard. This is because the critical bandwidth at 100Hz is >about 80Hz, and the two tones would be within the same critical band; one >will only hear two distinct tones when the two excitations exist in >separate critical bands. Hence there is no point in having controllable >bands which are finer in resolution than a critical band. > >Vinay S.N (M.Phil, M.Sc) > >Doctoral Student in Audiology, > >AIISH, Mysore - 6. > > ----- Original Message ----- > From: "Richard H." > To: AUDITORY(at)LISTS.MCGILL.CA > Subject: Critical bands v hearing loss > Date: Wed, 21 Sep 2005 15:14:00 +0100 > >Hi, In hearing aids & similar band-based audio processors, is there >likely to be any point in having controllable bands which are finer in >resolution than a critical band? Thanks, regards, Richard


This message came from the mail archive
http://www.auditory.org/postings/2005/
maintained by:
DAn Ellis <dpwe@ee.columbia.edu>
Electrical Engineering Dept., Columbia University