EMUSIC-L Digest Volume 64, Issue 16 This issue's topics: Human ear sensivity ? (3 messages) SUMMARY:Human ear sensitivity. Your EMUSIC-L Digest moderator is Joe McMahon . You may subscribe to EMUSIC-L by sending mail to listserv@american.edu with the line "SUB EMUSIC-L your name" as the text. The EMUSIC-L archive is a service of SunSite (sunsite.unc.edu) at the University of North Carolina. ------------------------------------------------------------------------ Date: Mon, 9 May 1994 17:46:27 +0300 From: Argiris Kranidiotis Subject: Human ear sensivity ? Dear Netters, Two things: -I am looking for a mathematical (or other) model of the sensivity of the human ear over different frequencies. -Better yet , I'd like to know if there exists a kind of psychoacoustic norm which would give the distance of two spectra (i.e. How two spectra sound same to humans) Please respond directly to me via e-mail. If there is enough interest I'll post a summary later. Any help would be appreciated. Argiris A. Kranidiotis -- ____________________________ __________________________________ / /\ / /\ / Argiris A. Kranidiotis _/ /\ / E-mail (Internet): _/ /\ / University Of Athens / \/ / / \/ / Informatics Department /\ / akra@zeus.di.uoa.ariadne-t.gr /\ /___________________________/ / /_________________________________/ / \___________________________\/ \_________________________________\/ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ------------------------------ Date: Mon, 9 May 1994 13:47:03 EDT From: David Lunney Subject: Re: Human ear sensivity ? A. Kranidiotis asks if the is a metric for how alike or different two spectra will sound, and if there is a math model for the response of the human ear. The answer to both questions is "no", to the best my knowledge (but I am not a perceptual psychologist). Every set of ears is different and they change with age. I have experimented on myself to see if sounds generated by infrared spectra could be distinguished auditorily, and have come across cases in which two waveforms LOOK different, but sound the same to me. I have dubbed this "the Rich Little effect" for the great impressionist. (Impressionists and their targets sound uncannily alike, but will look different on a spectrograph.) But I have a noise-induced hearing centered at 6 kHz. So the effect may not actually exist for people with more nearly normal hearing. I suggest that Mr. Kranidiotis start by reading a standard book on sound perception. Diana Deutsch's classic on music perception would be good beginning. David Lunney Department of Chemistry and Science Institute for the Disabled East Carolina University Greenvlle, NC 27858 USA VOICE: 919-757-6713 919-758-6453 FAX: 919-757-6210 CHLUNNEY@ECUVM1.BITNET CHLUNNEY@ECUVM.CIS.ECU.EDU ------------------------------ Date: Mon, 9 May 1994 16:26:07 EDT From: Brian Adamson Subject: Re: Human ear sensivity ? % A. Kranidiotis asks if the is a metric for how alike or different two % spectra will sound, and if there is a math model for the response of the % human ear. The answer to both questions is "no", to the best my % knowledge (but I am not a perceptual psychologist). Every set of ears is I went to a lecture a few years back where they were monitoring the auditory nerve of cats in response to sounds ... These were some U. of Maryland folks ... They may have a report or something from these experiments. This included investigation of how the cats' brains received information on sounds of different pitches and of different relative positions ... This may be of interest to Mr. Kranidiotis ... I think this was in conjunction with some Art. Intell. (Comp. Sci) work at MD ...perhaps with the psychology dept. as well .... % different and they change with age. I have experimented on myself to see % if sounds generated by infrared spectra could be distinguished % auditorily, and have come across cases in which two waveforms LOOK % different, but sound the same to me. I have dubbed this "the Rich Little % effect" for the great impressionist. (Impressionists and their targets % sound uncannily alike, but will look different on a spectrograph.) % % But I have a noise-induced hearing centered at 6 kHz. So the effect may % not actually exist for people with more nearly normal hearing. % % I suggest that Mr. Kranidiotis start by reading a standard book on sound % perception. Diana Deutsch's classic on music perception would be good % beginning. % % David Lunney % Department of Chemistry and % Science Institute for the Disabled % East Carolina University % Greenvlle, NC 27858 USA % VOICE: 919-757-6713 919-758-6453 % FAX: 919-757-6210 % CHLUNNEY@ECUVM1.BITNET % CHLUNNEY@ECUVM.CIS.ECU.EDU Brian ___________________________________________________________________ R. Brian Adamson Information Technology Division adamson@itd.nrl.navy.mil Naval Research Laboratory NRL Code 5523 Washington, DC 20375 ------------------------------ Date: Tue, 10 May 1994 13:41:20 +0300 From: Argiris Kranidiotis Subject: SUMMARY:Human ear sensitivity. ******************************************** * HUMAN EAR SENSITIVITY SUMMARY OF ANSWERS * ******************************************** -A big thanks to all those kind people who responded. -It seems to be an very interesting subject for many people, so here it is an edited summary of what I've received so far (about 48 hours)... -My comments are put in square brackets [ ]. ------------------------------------------------------------------------ Question #1: How humar ear responds to various frequencies ? ------------------------------------------------------------------------ From: Various people ------------------------------------------------------------------------ -Flecher-Munson curves (the most popular answer). Peak sensitivity at 3,300 Hz , falling off below 40 Hz, and above 10 kHz. [ Yes they are really popular. I've searched some books of physics and speech processing and I found those nice curves... The problem is that I found only graphs and no numerical data. >From the volume of mail I received , I think that it could be benefit for many people , if someone could provide NUMERICAL DATA about Flecher-Muchon curves.If someone has the data but it thinks that it would be very time consuming for him to type , I suggest to send me some scanned pages of data and I'll post the numbers here. What do you think ? -- AK ] -"An Introduction to the Psychology of Hearing". By Moore , 3d edition. (the most popular reference). From: Vincent Pagel ------------------------------------------------------------------------ The first thing you're looking for is an ISOSONIC curve : it's a family of curves a bit like this: Db ^| || | | \ | | | | | \ / | | / | \________ ______/ | \___/ | | |_________________________________________________> Frequency (Hz) 400 2500 6000 10000 20000 PERCEPTUALLY all the sounds corresponding to the points on the curve have the same intensity : this means that the hear have a large range where it is nearly linear ( 1000 to 8000 Hz ), achieving better result on a little domain ( around 3000 Hz if my memory serves). [ the curve has a minimum at 3,300 Hz -- AK ] The rate drops dramatically after 10000 Hz and before 500 Hz ). You can draw different isosonic curves depending on the first intensity you begin with ( e.g. if the intensity at 2500Hz is 50 db you get one curve, but if you start at 2500 Hz with 70 db you get another isosonic curve .... generally isosonic curves have nearly the same shape and it does not depend too much on the point it begins at) To my knowledge there is no mathematic formula given to approximate isosonic curves, but with the data in the book by Moor it should not be very difficult to find an approximation. From: Angelo Campanella ------------------------------------------------------------------------ Obtain the ISO "Zero Phons" standard threshold of human hearing. [ I thought about this too, but I didn't found any info at the net -- AK] It is 0 dB, of course at 1,000 Hz. My brief data is - for lower frequencies - Monaural Binaural 31 Hz 75 57 63 Hz 52 34 125 " 36 23 250 " 24 .. From: walkow@compsci.bristol.ac.uk (Tomasz Walkowiak) ------------------------------------------------------------------------ The equal loudness curve can be aproximated by: E(w)=1.151*SQRT( (w^2+144*10^4)*w^2/((w^2+16*10^4)*(w^2+961*10^4)) ) From: Robinson et al.: Br.J.A.Phys. 7, 166-181, 1956. [ This is the only formula I've received , BUT there is no hint about what E(w) , w is . I think that it gives Loudness vs Amplitude and *NOT* Loudness vs Frequency -- AK] ------------------------------------------------------------------------- Question #2: Phychoacoustic norm or Timbral Metric ? ------------------------------------------------------------------------- From: Christopher John Rolfe ------------------------------------------------------------------------- Grey, J.M. "Multidimensional Perceptual Scaling of Musical Timbres" Journal of the Acoustical Soceiety of America, 63, 1493-1500. Metrics have a long tradition in the literature, beginning with Fechner in the 19th Century. Cognitive science, however, points out that perceptual space may be non-Euclidean. In other words, there is NO simple metric. Repp, B.H (1984) "Categorical perception: Issues, methods, findings" In N.J. Lass (ed.) Speech and Language: Advances in Basic Research and Practice. Vol. 10. 1249-1257. From: Fahey@psyvax.psy.utexas.edu (Richard Fahey) -------------------------------------------------------------------------- These curves [Letcher-Munson again...--AK] may be used to normalise spectra for loudness at different frequencies (changing dB into phons), and with a further change into sones one obtains a loudness density plot. The plot can be made more psychologically real by changing the frequency scale to the Bark scale, and using an auditory filter to smear the spectrum. The distance between two spectra represented in ways similar to this can be calculated as a Euclidean distance, and compared with psychoacoustic data. From: Vincent Pagel -------------------------------------------------------------------------- The second thing you're looking for, is curves corresponding to the MASKING effect: those curves show the minimal intensity a sound with a given frequency must have to be percieved, when played simultaneously with a sound having a constant frequency during the experiment ( e.g. let's say that you want to find out the masking effect of a 500 Hz frequency .... you'll play it for exemple a 50 db .... and at the same time you'll play another frequency and you adjust the level of the second frequency to find out the limen where it is percieved. For exemple a sound played at 1000 Hz have to be louder than a sound at 700 Hz, because it's an harmonic of the masking frequency of 500 Hz ). PERHAPS YOU CAN FIND INFORMATIONS ON THIS BY READING THE FAQ ON THE MPEG COMPRESSION STANDARD, as it is based on those psychoacoustic datas.... [Very interesting idea , can anyone provide more info there ? -- AK] But I doubt that you'll found a formula in the FAQ, to find it you'll have to look into the source code of an MPEG II compressor ! You can find it by anonymous FTPing on sunsite.unc.edu and by looking in the IUMA archive , they have sources for MPEG II compression and decompression ---------------------------------------------------------------------------- REFERENCES / BOOKS ---------------------------------------------------------------------------- %Q Fry R.B. %T Measurement of Specific Sequence Effects in Loudness Perception %I PhD Dissertation, Duke University %D 1981 %Q Lane H.L., Catania A.C., Stevens S.S. %T Voice Level: Autophonic Scale, Perceived Loudness, and Effects of Sidetone %J JASA %V 33 %N 2 %P 160-167 %D 1961 %Q Peterson G E, McKinney N P %T The measurement of speech power %J Phonetica %V 7 %P 65-84 %D 1961 %Q Schlauch R.S., Wier C.C. %T A Method for Relating Loudness-Matching and Intensity-Discrimination Data %J Journal of Speech and Hearing Research %V 30 %P 13-20 %D 1987 %Q Small AM, Brandt JF, Cox PG %T Loudness as a function of signal duration %J JASA %V 34 %P 513-514 %D 1962 %Q Stevens S.S. %T Calculation of the Loudness of Complex Noise %J JASA %V 28 %N 5 %P 807-832 %D 1956 A.S.Bregman, Auditory Scene Analysis, MIT Press, 1990 Stephen Handel, Listening, [sorry, no citation] Grey, J.M. "Multidimensional Perceptual Scaling of Musical Timbres" Journal of the Acoustical Soceiety of America, 63, 1493-1500. Repp, B.H (1984) "Categorical perception: Issues, methods, findings" In N.J. Lass (ed.) Speech and Language: Advances in Basic Research and Practice. Vol. 10. 1249-1257. Moore and Glasberg, JASA 74(3) 1983. Bladon and Lindblom, JASA 69(5) 1981. J. R. Pierce, _The Science of Musical Sound_ (Freenam, New York, 1983). J. G. Roederer, _Introduction to the Physics and Psychophysics of Music_ (Springer-Verlag, New York, 1975). S. S. Stevens, "Measurement of Loudness", _J. Acoust. Soc. Amer. 27_ (1955): 815 S. S. Stevens, "Neural Events ans Psyhcophysical Law", _Science 170_ (1970): 1043 E. Zwicker, G. Flottorp, and S. S. Stevens, "Critical Bandwidth in Loudness Summation", _J. Acoust. Soc. Amer. 29_ (1957): 548 @article{herm90, author={Hynek Hermansky}, institution={Speech Technology Laboratory, Division of Panasonic Technologies, Inc., 3888 State Street, Santa Barbara, CA 93105, USA}, title={Perceptual linear predictive ({PLP}) analysis of speech}, journal={J. Acoust. Soc. Am.}, year={1990}, volume={87}, number={4}, pages={1738--1752}, month={April}, abstract={A new technique for the analysis of speech, the perceptual linear predictive (PLP) technique, is presented and examined. This technique uses three concepts from the psychophysics of hearing to derive an estimate of the auditory spectrum: (1) the critical-band spectral resolution, (2) the equal-loudness curve, and (3) the intensity-loudness power law. The auditory spectrum is then approximated by an autoregressive all-pole model. A 5th-order all-pole model is effective in suppressing speaker-dependent details of the auditory spectrum. In comparison with conventional linear predictive (LP) analysis, PLP analysis is more consistent with human hearing. The effective second formant F2' and the 3.5-Bark spectral-peak integration theories of vowel perception are well accounted for. PLP analysis is computationally efficient and yields a low-dimensional representation of speech. These properties are found to be useful in speaker-independent automatic-speech recognition.}, } Name: "An Introduction to the Physiology of Hearing" Author: James O. Pickles,Dept. of Physiology,Uni. Birmingham,England. Publisher: Academic Press,1982. ISBN 0-12-554750-1 (hardback) ISBN 0-12-554752-8 (paperback). "An introduction to the psychology of hearing" by B. MOORE , 3d Edition. ---------------------------------------------------------------------------- Acknowledgements ---------------------------------------------------------------------------- Many thanks to the following people that contributed to this summary: Angelo Campanella WITOLD Andrew Hunt Christopher John Rolfe Brian Adamson "Goodknight, Greg" David Lunney Fahey@psyvax.psy.utexas.edu (Richard Fahey) xrjdm@dirac.gsfc.nasa.gov (Joe McMahon) Colin_T._Smith@BOPS.VOA.GOV ldcolton@cse.ogi.edu (L Don Colton) turlough@odyssey.ucc.ie walkow@compsci.bristol.ac.uk Vincent Pagel -- ____________________________ __________________________________ / /\ / /\ / Argiris A. Kranidiotis _/ /\ / E-mail (Internet): _/ /\ / University Of Athens / \/ / / \/ / Informatics Department /\ / akra@zeus.di.uoa.ariadne-t.gr /\ /___________________________/ / /_________________________________/ / \___________________________\/ \_________________________________\/ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ------------------------------ End of the EMUSIC-L Digest ******************************