Subject: Re: Autocorrelation From: Bob Carlyon <bob.carlyon(at)MRC-CBU.CAM.AC.UK> Date: Wed, 19 Jul 2000 10:37:53 +0100christian, thanks for posting the URL. I liked the demo. One thing which struck me is that even the random pulse trains seem to have a (weak) pitch. It sounds very much like what happens when you mix two unresolved groups of harmonics (having harmonically unrelated F0s) in the same frequency region (Carlyon, JASA, vol 102, p1097-1105 [1997]). In that paper I provided evidence for another cue for temporal pitch perception, in which the average rate of pulses in the composite waveform formed the basis for pitch judgements. Indeed, one can successively reduce the pitch of a bandpass filtered pulse train (whose harmonics are unresolved by the peripheral auditory system) by deleting a greater and greater proportion of those pulses (with the deleted pulses being selected at random) cheers bob PS I am cc'ing this to the auditory list, as I feel like a bit of blatant self-promotion today. I must confess to not having followed all of the previous discussion (I was just lured by the prospect of listening to your sounds), so if my comments are not strictly relevant then I apologise Dr. Bob Carlyon MRC Cognition and Brain Sciences Unit 15 Chaucer Rd. Cambridge CB2 2EF England Phone: (44) 1223 355294 ext 720 Fax: (44) 1223 359062 NOTE NEW EMAIL ADDRESS: bob.carlyon(at)mrc-cbu.cam.ac.uk