Re: [AUDITORY] Number of critical bands in human hearing? (Pierre Divenyi )


Subject: Re: [AUDITORY] Number of critical bands in human hearing?
From:    Pierre Divenyi  <pdivenyi@xxxxxxxx>
Date:    Fri, 15 Sep 2023 08:27:53 -0700

--Apple-Mail-986DEE69-E3A1-480A-B5D0-A060F1E7A2D1 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Nicolas, Your idea cuts through the unnecessary maze. I like it also because it does n= ot make me think of this question every time I put my hand on the piano keyb= oard which is tuned like =E2=80=A6. what? Can you tell me? Best, Pierre Pardon my typos. It's Apple's fault.=20 > On Sep 15, 2023, at 00:02, Nicolas Grimault <nicolas.grimault@xxxxxxxx> wro= te: >=20 > =EF=BB=BF > Dear, >=20 > As previously said, auditory band is a continuum and could be defined at a= ny poit of the cochlea, I think the original question should be reformulated= as: >=20 > "How maby independent auditory bands do we have within the range of audibi= lity?" >=20 > Best. >=20 > Nicolas. >=20 >=20 >=20 >=20 >=20 > Le 15/09/2023 =C3=A0 06:17, James Johnston a =C3=A9crit : >> A "critical band" or better an "ERB" is defined at any point on the cochl= ea. >>=20 >> The "number" of them is therefore an odd question. If you stack ERB's ne= xt to each other, that's a more meaningful question, but even then what happ= ens at low frequencies is still under some debate the last I've seen. >>=20 >> So, maybe the question of "translate ERB to Frequency Range" is a better q= uestion, and then you can stack them end to end if you must, but speaking as= someone who has written a lot of different masking threshold calculations f= or various audio codecs, you really need to have much finer resolution than t= hat, and then handle the "overlap" so that for any given frequency, you're c= lose to using an ERB centered at that frequency. Even 'centered' is a bit of= a tricky question since you'd like to have some invariance of shape across d= ifferent centers, but that's more than I want to write at 11PM tonight. :) >>=20 >> On Thu, Sep 14, 2023 at 9:12=E2=80=AFPM Smits, J.C.M. (Cas) <c.smits@xxxxxxxx= erdamumc.nl> wrote: >>> The number of 24 CB refers (probably) to the Bark scale (Zwicker 1961, J= ASA). But it covers only the frequencies upto 15.5 kHz. So you need a few mo= re to get to 20 kHz=E2=80=A6 >>>=20 >>> =20 >>>=20 >>> Best, >>>=20 >>> Cas Smits >>>=20 >>> =20 >>>=20 >>> Van: AUDITORY - Research in Auditory Perception <AUDITORY@xxxxxxxx= A> Namens Richard F. Lyon >>> Verzonden: 14 September 2023 07:21 >>> Aan: AUDITORY@xxxxxxxx >>> Onderwerp: Re: Number of critical bands in human hearing? >>>=20 >>> =20 >>>=20 >>> I think critical bands are not discrete countable things. >>>=20 >>> But if you want to divide up the range of 20 Hz to 20 kHz into CB-size b= ands, then there should be an answer, though it will be more at low sound le= vels than at high sound levels. 24 sounds plausible for moderate sound leve= l. If you count ERBs at low level, you'll get more than that, maybe about 4= 0. >>>=20 >>> Dick >>>=20 >>> =20 >>>=20 >>> =20 >>>=20 >>> On Wed, Sep 13, 2023 at 9:14=E2=80=AFPM David Jackson Morris <dmorris@xxxxxxxx= m.ku.dk> wrote: >>>=20 >>> Dear all, >>>=20 >>> =20 >>>=20 >>> In teaching an undergrad course on hearing science the students have ask= ed, how many critical bands are there in normal healthy hearing? The text th= at we use says that there are 24. If I ask ChatGPT it also cites Fletcher a= nd Munson=E2=80=99s estimation of 24, but what would it know. . . =20 >>>=20 >>> =20 >>>=20 >>> Am I right in suspecting that this may have been revised upwards at some= stage (?). Is the collective wisdom of the list able to help with this or p= oint to an authoritative source?=20 >>>=20 >>> =20 >>>=20 >>> Cheers >>>=20 >>> David >>>=20 >>> =20 >>>=20 >>> =20 >>>=20 >>> David Jackson Morris, PhD, LTCL >>>=20 >>> Associate Professor/Lektor >>>=20 >>> =20 >>>=20 >>> University of Copenhagen/K=C3=B8benhavns Universitet >>>=20 >>> Speech Pathology and Audiology/Audiologop=C3=A6di >>>=20 >>> Department of Nordic Studies and Linguistics/Institut for Nordiske Studi= er og Sprogvidenskab >>>=20 >>> Emil Holms Kanal 2 >>>=20 >>> 2300 Copenhagen S/K=C3=B8benhavn S >>>=20 >>> =20 >>>=20 >>> Department Homepage >>>=20 >>> =20 >>>=20 >>> =20 >>>=20 >>> - >>>=20 >>> =20 >>>=20 >>> S=C3=A5dan beskytter vi persondata >>>=20 >>> =20 >>>=20 >>> =20 >>>=20 >>> ______________________________________________________ >>> AmsterdamUMC disclaimer : www.amsterdamumc.org/disclaimers >>>=20 >>=20 >>=20 >> --=20 >> James D. (jj) Johnston >>=20 >> Chief Scientist, Immersion Networks > --=20 > ------------------------------------------------------------------- > Nicolas Grimault > Cognition Auditive et Psychoacoustique > UMR CNRS 5292 Centre de Recherche en Neurosciences de Lyon > Centre Hospitalier Le Vinatier - B=C3=A2timent 462 - Neurocampus > 95 boulevard Pinel > 69675 Bron Cedex > France > Vocal: 33 (0)4 81 10 65 73 > Email: nicolas.grimault@xxxxxxxx > ___.-----.______ = =20 > ___.-----'::::::::::::::::`---.___ = _ _ > _.--._ (:::;,-----'~~~~~`----::::::::::.. `-. = ,-(|)--(|)-. > _ .'_---. `--.__ `~~' `~`--.:::::`.. `..= \_ .. _/ > ; `-.____.-' ' {0} ` `--._`---.____ `:::::::: : := : \______/ > :_^ ~ `--.___ `----.__`----.____ ~::::::.`;'= : V V ____ > :`--.__,-----.___( `---.___ `---.___ `----.___ ~|;:,' : |= `.^^`. /^,--` > `-.___,---.____ _, ._ `----.____ `----.__ `-----.___;--' ; := \^^^\ (^^\ > `---' `. `._ `)) , , , `----.____.----.____ --' := | |^^^| _,-._ \^^\ > / `,--.\ `.` ` ` ` , , , _.-- `-----'|= ' (^^^^\ __ _,-'^^^^^`. _,'^^)= > _.~~~~~~._____ __./'_/' : .:----.___ ` ` ` `` .-' , , :::'= \^^^^`._,-'^^`-._.'^^^^__^^^^ `--'^^^_/ > ///--\; ____ : :' ____`---.___.--:: , ` ` ::' = \^^^^^ ^^^_^^^^^^^_,-' `.^^^^^^^^_/ > `' _.' ( /______ ( `-._ `-._,-' = `.____,-' `-.__.' `-.___.' > .-' __.-// /_______---' `-._ `. > ~~~ ///// `' ~~~~~~ ~~ ______; ::. > `'`' /_______ _.' > , ~~~ ~~~~~~~~ /___.---' --__= > ` ~~~ >=20 >=20 >=20 > ___ ___ > ( _< >_ ) c~~p ,---------.=20 > // \\ ,---'oo ) \ =20 > \\___..___// ( O O )/ > `-( )-' `=3D^=3D' / > _|__|_ \ , . / > /_|__|_\ \\ |-----'| / =20 > /_|__|_\ ||__| |_|__| > /_\__/_\ > \ || / _) > || ( ) > \\___// > `---' >=20 >=20 > =20 > =20 > =20 > =20 >=20 >=20 > ------------------------------------------------------------------- --Apple-Mail-986DEE69-E3A1-480A-B5D0-A060F1E7A2D1 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable <html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D= utf-8"></head><body dir=3D"auto">Nicolas,<div><br></div><div>Your idea cuts t= hrough the unnecessary maze. I like it also because it does not make me thin= k of this question every time I put my hand on the piano keyboard which is t= uned like =E2=80=A6. what? Can you tell me?</div><div><br></div><div>Best,</= div><div>Pierre<br><br><div dir=3D"ltr">Pardon my typos. It's Apple's fault.= &nbsp;</div><div dir=3D"ltr"><br><blockquote type=3D"cite">On Sep 15, 2023, a= t 00:02, Nicolas Grimault &lt;nicolas.grimault@xxxxxxxx&gt; wrote:<br><br></b= lockquote></div><blockquote type=3D"cite"><div dir=3D"ltr">=EF=BB=BF =20 <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DUTF-8"= > =20 =20 <p>Dear,</p> <p>As previously said, auditory band is a continuum and could be defined at any poit of the cochlea, I think the original question should be reformulated as:</p> <p>"How maby <b>independent</b> auditory bands do we have within the range of audibility?"</p> <p>Best.<br> </p> <p>Nicolas.</p> <p><br> </p> <p><br> </p> <div class=3D"moz-cite-prefix">Le 15/09/2023 =C3=A0 06:17, James Johnsto= n a =C3=A9crit&nbsp;:<br> </div> <blockquote type=3D"cite" cite=3D"mid:CAO2qRdMi=3DQoaybG0rwbM8e-CmefBV9_= zFiX--yfdnq4DbU4ohg@xxxxxxxx"> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DUTF-= 8"> <div dir=3D"ltr"> <div> <div>A "critical band" or better an "ERB" is defined at any point on the cochlea.<br> <br> </div> The "number" of them is therefore an odd question.&nbsp; If you stack ERB's next to each other, that's a more meaningful question, but even then what happens at low frequencies is still under some debate the last I've seen.<br> <br> </div> So, maybe the question of "translate ERB to Frequency Range" is a better question, and then you can stack them end to end if you must, but speaking as someone who has written a lot of different masking threshold calculations for various audio codecs, you really need to have much finer resolution than that, and then handle the "overlap" so that for any given frequency, you're close to using an ERB centered at that frequency. Even 'centered' is a bit of a tricky question since you'd like to have some invariance of shape across different centers, but that's more than I want to write at 11PM tonight. :)<br> </div> <br> <div class=3D"gmail_quote"> <div dir=3D"ltr" class=3D"gmail_attr">On Thu, Sep 14, 2023 at 9:12=E2=80=AFPM Smits, J.C.M. (Cas) &lt;<a href=3D"mailto:c.smits@xxxxxxxx= amsterdamumc.nl" moz-do-not-send=3D"true" class=3D"moz-txt-link-freetext">c.= smits@xxxxxxxx</a>&gt; wrote:<br> </div> <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> <div class=3D"msg-2434205711684206654"> <div lang=3D"NL"> <div class=3D"m_-2434205711684206654WordSection1"> <p class=3D"MsoNormal"><span style=3D"font-size:11pt;font-fa= mily:&quot;Calibri&quot;,sans-serif;color:rgb(31,73,125)" lang=3D"EN-GB">The= number of 24 CB refers (probably) to the Bark scale (Zwicker 1961, JASA). But it covers only the frequencies upto 15.5 kHz. So you need a few more to get to 20 kHz=E2=80=A6</span></p> <p class=3D"MsoNormal"><span style=3D"font-size:11pt;font-fa= mily:&quot;Calibri&quot;,sans-serif;color:rgb(31,73,125)" lang=3D"EN-GB">&nb= sp;</span></p> <p class=3D"MsoNormal"><span style=3D"font-size:11pt;font-fa= mily:&quot;Calibri&quot;,sans-serif;color:rgb(31,73,125)" lang=3D"EN-GB">Bes= t,</span></p> <p class=3D"MsoNormal"><span style=3D"font-size:11pt;font-fa= mily:&quot;Calibri&quot;,sans-serif;color:rgb(31,73,125)" lang=3D"EN-GB">Cas= Smits</span></p> <p class=3D"MsoNormal"><span style=3D"font-size:11pt;font-fa= mily:&quot;Calibri&quot;,sans-serif;color:rgb(31,73,125)" lang=3D"EN-GB">&nb= sp;</span></p> <p class=3D"MsoNormal"><b><span style=3D"font-size:11pt;font= -family:&quot;Calibri&quot;,sans-serif">Van:</span></b><span style=3D"font-s= ize:11pt;font-family:&quot;Calibri&quot;,sans-serif"> AUDITORY - Research in Auditory Perception &lt;<a href=3D= "mailto:AUDITORY@xxxxxxxx" target=3D"_blank" moz-do-not-send=3D"true"= class=3D"moz-txt-link-freetext">AUDITORY@xxxxxxxx</a>&gt; <b>Namens </b>Richard F. Lyon<br> <b>Verzonden:</b> 14 September 2023 07:21<br> <b>Aan:</b> <a href=3D"mailto:AUDITORY@xxxxxxxx" t= arget=3D"_blank" moz-do-not-send=3D"true" class=3D"moz-txt-link-freetext">AU= DITORY@xxxxxxxx</a><br> <b>Onderwerp:</b> Re: Number of critical bands in human hearing?</span></p> <p class=3D"MsoNormal">&nbsp;</p> <div> <div> <p class=3D"MsoNormal">I think critical bands are not discrete countable things.</p> </div> <div> <p class=3D"MsoNormal">But if you want to divide up the range of 20 Hz to 20 kHz into CB-size bands, then there should be an answer, though it will be more at low sound levels than at high sound levels.&nbsp; 24 sounds plausible for moderate sound level.&nbsp; If you count ERBs at low level, you'll ge= t more than that, maybe about 40.</p> </div> <div> <p class=3D"MsoNormal">Dick</p> </div> <div> <p class=3D"MsoNormal">&nbsp;</p> </div> </div> <p class=3D"MsoNormal">&nbsp;</p> <div> <div> <p class=3D"MsoNormal">On Wed, Sep 13, 2023 at 9:14=E2=80= =AFPM David Jackson Morris &lt;<a href=3D"mailto:dmorris@xxxxxxxx= .ku.dk" target=3D"_blank" moz-do-not-send=3D"true" class=3D"moz-txt-link-fre= etext">dmorris@xxxxxxxx</a>&gt; wrote:</p> </div> <blockquote style=3D"border-width:medium medium medium 1pt;border-style:none none none solid;border-color:currentcolor currentcolor currentcolor rgb(204,204,204);padding:0cm 0cm 0cm 6pt;margin:5pt 0cm 5pt 4.8pt"> <div> <div> <div> <p class=3D"MsoNormal"><span lang=3D"EN-US">Dear all,</span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">&nbsp;= </span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">In teaching an undergrad course on hearing science the students have asked, how many critical bands are there in normal healthy hearing? The text that we use says that there are 24.&nbsp; &nbsp;If I ask ChatGPT it a= lso cites Fletcher and Munson=E2=80=99s estimation= of 24, but what would it know. . . &nbsp;</span><= span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">&nbsp;= </span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">Am I right in suspecting that this may have been revised upwards at some stage (?).&nbsp; Is the collective wisdom of the list able to help with this or point to an authoritative source?&nbsp; </span><span lang=3D= "DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">&nbsp;= </span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">Cheers= </span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">David<= /span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">&nbsp;= </span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal"><span lang=3D"EN-US">&nbsp;= </span><span lang=3D"DA"></span></p> <div> <div> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <b><span style=3D"font-size:7.5pt;font-famil= y:&quot;Verdana&quot;,sans-serif;color:gray" lang=3D"EN-US">David Jackson Mo= rris, PhD, LTCL</span></b><span lang=3D"DA"></= span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"EN-US">Associate Professor/Lektor</span><span lang=3D"DA"><= /span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"EN-US">&nbsp;</span><span l= ang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <b><span style=3D"font-size:7.5pt;font-famil= y:&quot;Verdana&quot;,sans-serif;color:gray" lang=3D"EN-US">University of Copenhagen/K=C3=B8benhavns Universitet</= span></b><span lang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"EN-US">Speech Pathology an= d Audiology/Audiologop=C3=A6di</span><span l= ang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">Department of Nordic S= tudies and Linguistics/Institut for Nordiske Studier og Sprogvidenskab</span><span lang= =3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"SV">Emil Holms Kanal 2</sp= an><span lang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">2300 Copenhagen S/K=C3= =B8benhavn S</span><span lang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">&nbsp;</span><span lan= g=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA"><a href=3D"https://nor= s.ku.dk/english/staff/?pure=3Den/persons/398661" target=3D"_blank" moz-do-no= t-send=3D"true"><span style=3D"color:rgb(5,99,193)">Department Homepage</span></a></span><span lang=3D= "DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">&nbsp;</span><span lan= g=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">&nbsp;</span><span lan= g=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:12= pt"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">&nbsp; -</span><span l= ang=3D"DA"></span></p> <p class=3D"MsoNormal" style=3D"line-height:8p= t"> <span style=3D"font-size:7.5pt;font-family:&= quot;Verdana&quot;,sans-serif;color:gray" lang=3D"DA">&nbsp;</span><span lan= g=3D"DA"></span></p> <p class=3D"MsoNormal"><span style=3D"color:bl= ack" lang=3D"DA"><a href=3D"https://informationssikkerhed.ku.dk/persondatabe= skyttelse/privatlivspolitik/" target=3D"_blank" moz-do-not-send=3D"true"><sp= an style=3D"font-size:7.5pt;font-family:&quot;Verdana&quot;,sans-serif;color= :gray;text-decoration:none">S=C3=A5dan beskytter vi persondata</span></a></sp= an><span lang=3D"DA"></span></p> </div> </div> <p class=3D"MsoNormal"><span lang=3D"DA">&nbsp;</s= pan></p> <p class=3D"MsoNormal"><span lang=3D"DA">&nbsp;</s= pan></p> </div> </div> </div> </blockquote> </div> <p class=3D"MsoNormal" style=3D"text-align:center" align=3D"= center"><span style=3D"font-size:7pt;font-family:&quot;Trebuchet MS&quot;,sans-serif;color:black">_______________________= _______________________________<br> AmsterdamUMC disclaimer : <a href=3D"http://www.amsterda= mumc.org/disclaimers" target=3D"_blank" moz-do-not-send=3D"true">www.amsterd= amumc.org/disclaimers</a></span></p> </div> </div> </div> </blockquote> </div> <br clear=3D"all"> <br> <span class=3D"gmail_signature_prefix">-- </span><br> <div dir=3D"ltr" class=3D"gmail_signature"> <div dir=3D"ltr"> <div>James D. (jj) Johnston</div> <div><br> </div> <div>Chief Scientist, Immersion Networks<br> </div> </div> </div> </blockquote> <pre class=3D"moz-signature" cols=3D"72">--=20 ------------------------------------------------------------------- Nicolas Grimault Cognition Auditive et Psychoacoustique UMR CNRS 5292 Centre de Recherche en Neurosciences de Lyon Centre Hospitalier Le Vinatier - B=C3=A2timent 462 - Neurocampus 95 boulevard Pinel 69675 Bron Cedex France Vocal: 33 (0)4 81 10 65 73 Email: <a class=3D"moz-txt-link-abbreviated" href=3D"mailto:nicolas.grimault= @xxxxxxxx">nicolas.grimault@xxxxxxxx</a> ___.-----.______ = =20 ___.-----'::::::::::::::::`---.___ = _ _ _.--._ (:::;,-----'~~~~~`----::::::::::.. `-. = ,-(|)--(|)-. _ .'_---. `--.__ `~~' `~`--.:::::`.. `.. = \_ .. _/ ; `-.____.-' ' {0} ` `--._`---.____ `:::::::: : :: = \______/ :_^ ~ `--.___ `----.__`----.____ ~::::::.`;': = V V ____ :`--.__,-----.___( `---.___ `---.___ `----.___ ~|;:,' : | = `.^^`. /^,--` `-.___,---.____ _, ._ `----.____ `----.__ `-----.___;--' ; : = \^^^\ (^^\ `---' `. `._ `)) , , , `----.____.----.____ --' :| = |^^^| _,-._ \^^\ / `,--.\ `.` ` ` ` , , , _.-- `-----'|' = (^^^^\ __ _,-'^^^^^`. _,'^^) _.~~~~~~._____ __./'_/' : .:----.___ ` ` ` `` .-' , , :::' = \^^^^`._,-'^^`-._.'^^^^__^^^^ `--'^^^_/ ///--\; ____ : :' ____`---.___.--:: , ` ` ::' = \^^^^^ ^^^_^^^^^^^_,-' `.^^^^^^^^_/ `' _.' ( /______ ( `-._ `-._,-' = `.____,-' `-.__.' `-.___.' .-' __.-// /_______---' `-._ `. ~~~ ///// `' ~~~~~~ ~~ ______; ::. `'`' /_______ _.' , ~~~ ~~~~~~~~ /___.---' --__ ` ~~~ ___ ___ ( _&lt; &gt;_ ) c~~p ,---------.=20 // \\ ,---'oo ) \ =20 \\___..___// ( O O )/ `-( )-' `=3D^=3D' / _|__|_ \ , . / /_|__|_\ \\ |-----'| / =20 /_|__|_\ ||__| |_|__| /_\__/_\ \ || / _) || ( ) \\___// `---' =20 =20 =20 =20 -------------------------------------------------------------------</pre> =20 </div></blockquote></div></body></html>= --Apple-Mail-986DEE69-E3A1-480A-B5D0-A060F1E7A2D1--


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