Subject: birdies/duration From: beaucham <beaucham@xxxxxxxx> Date: Thu, 16 Mar 2006 10:11:19 -0600I've heard that a couple of my posts might not have made it to everyone on the list. They didn't echo back to me or get on the archives. So here they are again. Let Dan Ellis know if you missed them the first time, as there might be a malfunction some place. Jim ******************************************************************** From: beaucham@xxxxxxxx Date: March 16, 2006 To: audio@xxxxxxxx Subject: Re: - "Birdies" Bob Masta said (in part): "Birdies" are little whistling sounds that are related to the program material, but are not harmonics of it. We've encountered "birdies" in upper harmonics when trying to separate voices from mixtures, using a strictly harmonic model. If the upper harmonics are perturbed even slightly from their "proper" amplitudes, they tend to audibly stick out, causing this type of artifact. We also call the effect "chattering". Jim Beauchamp Univ. of Illinois Urbana-Champaign ******************************************************************** From: beaucham@xxxxxxxx Date: March 16, 2006 To: massimo.grassi@xxxxxxxx Subject: Re: Minimum duration required in a sinusoid to hear pitch cc: auditory@xxxxxxxx This is fine, but the question was specifically about sinusoids. This has been covered extensively in the literature, although apparently it is not as cut and dried as one might expect. Results will depend on factors such as frequency of sinusoid, duration, amplitude envelope, and peak SPL. Right now I'm looking at Wm. Hartmann's book, Signals, Sound, and Sensation, pp. 317-320. He refers to Moore, B.C.J. (1973). "Frequency difference limens for short duration tones", J. Acoutst. Soc. Am. 54, 610-619. At f=1000 Hz, duration .010 s, the frequency limen is about 6 Hz, giving an "uncertainty product" .010x6 = .06, which is very low compared to what a frequency counter can do. However, even this does not get at the question "minimum duration ... to hear pitch". What is meant by "hear pitch"? Hartmann goes further to say that Doughty and Garner (1947,1948) tested "click pitch" and "tone pitch", where the former allows the listener to identify "general frequency range" and the latter "mainly sounds like a click". A graph is given, which shows that 25 ms is required to a hear a tone pitch at 125 Hz but 10 ms is sufficient at or above 1000 Hz. Doughty, J.M. and Garner, W.R. (1947) "Pitch characteristics of short tones I--Two kinds of pitch threshold", J. Exp. Psych. 37, 351-365. Doughty, J.M. and Garner, W.R. (1948) "Pitch characteristics of short tones II--Pitch as a function of tonal duration", J. Exp. Psych. 38, 478-494. Perhaps another interpretation of "hear pitch" would be whether the listener could correctly identify a pitch within the 12-tone equal-tempered scale with some minimum duration sinusoid. I don't know if study has been done on this case. However, keep in mind that virtuostic musicians can play successive notes very fast, on the order of 10 to 20 per second, and "good listeners" think they know what they're hearing. Jim Beauchamp University of Illinois Urbana-Champaign Original message: >From: Massimo Grassi <massimo.grassi@xxxxxxxx> >Date: Wed, 15 Mar 2006 10:11:34 +0100 >To: AUDITORY@xxxxxxxx >Subject: Re: Minimum duration required in a sinusoid to hear pitch >Comments: To: Arturo Camacho <acamacho@xxxxxxxx> > >> I would like to know if there exists some research done about the >> minimum duration that a sinusoid has to have in order to hear pitch. >> Any reference to related literature will be highly appreciated. > >as far as I know there are two works but the timbre was complex: > >Robinson, K.L. and Patterson, R.D. (1995) "The duration required to identify >the instrument, the octave, or the pitch-chroma of a musical note," Music >Perception 13, 1-15. > >Robinson, K.L. and Patterson, R.D. (1995) "The stimulus duration required to >identify vowels, their octave, and their pitch-chroma," J. Acoust. Soc. >Am. 98, >1858-1865. > >The interesting result is that, when compared to vision, the auditory system >extracts first complex features (i.e. timbre) and later simple features (i.e. >octave and chroma). It seems that the visual system operates in the opposite >way (e.g. Marr, 1982): first simple features then complex features. > >I hope this helps, >m > >******************** >Massimo Grassi - PhD >Laboratorio di Psicologia >Via Petracco 8 - 33100 Udine - Italy >http://www.psy.unipd.it/~grassi >IMPORTANT! BEFORE SENDING REGULAR >MAIL PLEASE SEND AN EMAIL > >---------------------------------------------------------------------- >SEMEL (SErvizio di Messaging ELettronico) - CSIT -Universita' di Udine