Re: correction to post ("Beerends, J.G. (John)" )


Subject: Re: correction to post
From:    "Beerends, J.G. (John)"  <john.beerends@xxxxxxxx>
Date:    Tue, 2 Aug 2011 15:49:25 +0000
List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>

--_000_E64149642826D74489BC7362384E1BFC63BA31EXCMBX01tsntnonl_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Dear list, Periodicity plays a role in pitch perception but is not the whole story. In an experiment performed by Houtsma, many years ago, one sine goes to one= ear and another, harmonically related sine, to the other, there is no math= ematically periodicity at the fundamental, but melodies can be played using= this missing fundamental showing that a central processor finds the missin= g fundamental. John Beerends TNO ________________________________ From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxx= ILL.CA] On Behalf Of ita katz Sent: dinsdag 2 augustus 2011 16:56 To: AUDITORY@xxxxxxxx Subject: Re: correction to post Dear list, Isn't the 'missing fundamental' phenomenon is easily explained by the fact = that the auditory system recognizes periodicity (it is known that the audit= ory system preforms a time-domain analysis in addition to freq-domain analy= sis), and the periodicity is 'mathematically' there (i.e, no illusion whats= oever)? The periodicity is determined by the least-common-multiple of the periodici= ties of the present harmonics, so if (for example) a sound is composed of s= ines of frequencies 200Hz, 300Hz, and 400Hz, the periods are 5msec, 3 1/3ms= ec, and 2.5msec, so the least-common-multiple is 10msec (2 periods of 5msec= , 3 periods of 3.33msec, and 4 periods of 2.5msec), which is of course the = periodicity of the sum of the sines, or in other words 100Hz. (actually it = is the same as the greatest-common-divisor of the frequencies). Itamar Katz On Tue, Aug 2, 2011 at 5:13 PM, Ranjit Randhawa <rsran@xxxxxxxx<mailto:r= sran@xxxxxxxx>> wrote: Dear Nedra, In my opinion the most enduring (over 200 years) of all auditory "illusions= " is what has been called the "missing fundamental". The fact that this has= not been satisfactorily resolved by the tortured use of existing signal pr= ocessing techniques leads some, including yours truly, to believe that the = auditory system has figured out a unique way to do frequency analysis and t= o meet the dictum in biology that "form follows function". Taking into acco= unt where we are and the discussions that take place, e.g. this forum, it i= s interesting that there has been no discussion as to why the cochlear has = the shape it does. Therefore some experimental phenomenon that we may call = as an illusion, could have a very natural consequence of how frequency anal= ysis is done. One is lead to believe that we are truly very far from unders= tanding how the auditory system works and therefore hearing aid designs are= a bit of a hoax foisted on the "proletariat". Sorry if I sound a bit hars= h, but I think it is time people recognized that the emperor has not clothe= s. Regards, Randy Randhawa On 7/30/2011 3:16 AM, Nedra Floyd-Pautler, LLC wrote: My apologies for an over-active spell checker that changed "people" to "pro= letariat" in my recent posting. Below is the message I intended to send: I'm a science writer/audiologist researching an article on auditory illusio= ns. What value do they have "on the ground" for people with hearing deficit= s? Do what they tells us about the brain and hearing have application to he= aring aid design? Thank you, Nedra Floyd-Pautler www.thenedra.com<http://www.thenedra.com> This e-mail and its contents are subject to the DISCLAIMER at http://www.tn= o.nl/emaildisclaimer --_000_E64149642826D74489BC7362384E1BFC63BA31EXCMBX01tsntnonl_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dus-ascii"> <meta name=3D"GENERATOR" content=3D"MSHTML 8.00.6001.19046"> </head> <body> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial">Dear list,</font></span></div> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial"></font></span>&nbsp;</div> <span class=3D"430223615-02082011"> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial">Periodicity plays a role in pitch= perception but is not the whole story.&nbsp;</font></span></div> <div dir=3D"ltr" align=3D"left"><font color=3D"#0000ff" size=3D"2" face=3D"= Arial">In an experiment performed by Houtsma<span class=3D"430223615-020820= 11">,</span> many years ago<span class=3D"430223615-02082011">,</span> one = sine goes to one ear and another, harmonically related sine, to the other, there is no mathematically periodicity at the = fundamental, but melodies can be played&nbsp;using this missing fundamental= showing that a central processor finds the missing fundamental.</font></sp= an></div> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial"></font></span>&nbsp;</div> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial">John Beerends</font></span></div> <div dir=3D"ltr" align=3D"left"><span class=3D"430223615-02082011"><font co= lor=3D"#0000ff" size=3D"2" face=3D"Arial">TNO</font></span></div> <div dir=3D"ltr" lang=3D"en-us" class=3D"OutlookMessageHeader" align=3D"lef= t"> <hr tabindex=3D"-1"> <font size=3D"2" face=3D"Tahoma"><b>From:</b> AUDITORY - Research in Audito= ry Perception [mailto:AUDITORY@xxxxxxxx <b>On Behalf Of </b>ita katz<br> <b>Sent:</b> dinsdag 2 augustus 2011 16:56<br> <b>To:</b> AUDITORY@xxxxxxxx<br> <b>Subject:</b> Re: correction to post<br> </font><br> </div> <div></div> <div dir=3D"ltr">Dear list,<br> <br> Isn't the 'missing fundamental' phenomenon is easily explained by the fact = that the auditory system recognizes periodicity (it is known that the audit= ory system preforms a time-domain analysis in addition to freq-domain analy= sis), and the periodicity is 'mathematically' there (i.e, no illusion whatsoever)?<br> <br> The periodicity is determined by the least-common-multiple of the periodici= ties of the present harmonics, so if (for example) a sound is composed of s= ines of frequencies 200Hz, 300Hz, and 400Hz, the periods are 5msec, 3 1/3ms= ec, and 2.5msec, so the least-common-multiple is 10msec (2 periods of 5msec, 3 periods of 3.33msec, and 4 periods of 2.5= msec), which is of course the periodicity of the sum of the sines, or in ot= her words 100Hz. (actually it is the same as the greatest-common-divisor of= the frequencies).<br> <br> Itamar Katz<br> <br> <div class=3D"gmail_quote">On Tue, Aug 2, 2011 at 5:13 PM, Ranjit Randhawa = <span dir=3D"ltr"> &lt;<a href=3D"mailto:rsran@xxxxxxxx">rsran@xxxxxxxx</a>&gt;</span> w= rote:<br> <blockquote style=3D"BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex= ; PADDING-LEFT: 1ex" class=3D"gmail_quote"> <div text=3D"#000000" bgcolor=3D"#FFFFFF">Dear Nedra,<br> In my opinion the most enduring (over 200 years) of all auditory &quot;illu= sions&quot; is what has been called the &quot;missing fundamental&quot;. Th= e fact that this has not been satisfactorily resolved by the tortured use o= f existing signal processing techniques leads some, including yours truly, to believe that the auditory system has figured out= a unique way to do frequency analysis and to meet the dictum in biology th= at &quot;form follows function&quot;. Taking into account where we are and = the discussions that take place, e.g. this forum, it is interesting that there has been no discussion as to why the c= ochlear has the shape it does. Therefore some experimental phenomenon that = we may call as an illusion, could have a very natural consequence of how fr= equency analysis is done. One is lead to believe that we are truly very far from understanding how the audi= tory system works and therefore hearing aid designs are a bit of a hoax foi= sted on the &quot;proletariat&quot;.&nbsp; Sorry if I sound a bit harsh, bu= t I think it is time people recognized that the emperor has not clothes.<br> Regards,<br> Randy Randhawa<br> <br> On 7/30/2011 3:16 AM, Nedra Floyd-Pautler, LLC wrote:<br> <blockquote type=3D"cite"> <div style=3D"FONT-FAMILY: Arial; COLOR: #000000; FONT-SIZE: 12pt"><span st= yle=3D"FONT-FAMILY: monospace; FONT-SIZE: medium">My apologies for an over-= active spell checker that changed &quot;people&quot; to &quot;proletariat&q= uot; in my recent posting. Below is the message I intended to send:</span> <div><span style=3D"FONT-FAMILY: monospace; FONT-SIZE: medium"><br> </span></div> <div><span style=3D"FONT-FAMILY: monospace; FONT-SIZE: medium">I'm a scienc= e writer/audiologist researching an article on auditory illusions. What val= ue do they have &quot;on the ground&quot; for people with hearing deficits?= Do what they tells us about the brain and hearing have application to hearing aid design?&nbsp;<br> <br> Thank you,<br> Nedra Floyd-Pautler<br> <span style=3D"COLOR: rgb(0,0,139); TEXT-DECORATION: none"><a style=3D"COLO= R: rgb(0,0,139); TEXT-DECORATION: none" href=3D"http://www.thenedra.com" ta= rget=3D"_blank">www.thenedra.com</a></span></span></div> </div> </blockquote> </div> </blockquote> </div> <br> </div> <font face=3D"monospace">This e-mail and its contents are subject to the DI= SCLAIMER at http://www.tno.nl/emaildisclaimer</font></body> </html> --_000_E64149642826D74489BC7362384E1BFC63BA31EXCMBX01tsntnonl_--


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