Subject: Re: About importance of "phase" in sound recognition From: "reinifrosch@xxxxxxxx" <reinifrosch@xxxxxxxx> Date: Fri, 8 Oct 2010 09:41:15 +0000 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>------=_Part_1369_17538468.1286530875460 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hello James (et al.), I have not yet read Plomp and Sieeneken (1969), but shall do so as soon as = possible. In the meantime, my newest synthesizer experiment may be of some = interest: In the case of a one-octave two-tone (440 Hz, 880 Hz) composed of two sinus= oidal tones, I hear, both at the onset and later, no dependence of the loud= ness and the timbre on the delay (i.e., the phase) between the two tones, a= lthough the waveform of the complete signal does depend on that delay. Thes= e two sine tones form a harmonic complex tone, and the strengths of its two= partials are delay-independent. With two harmonic complex tones (harmonica voice), however, timbre and lou= dness of the one-octave two-tone vary from one try to the next. The variati= on is weaker than in the case of two equal frequencies. Constructive and de= structive interference among a part of the harmonics takes place.=20 The results for a one-just-fifth two tone (440 Hz, 660 Hz) are similar. The= variation of timbre and loudness in the case of harmonic complex tones is = now fairly weak, however.=20 Reinhart.=20 ----Urspr=C3=BCngliche Nachricht---- Von: jwbeauch@xxxxxxxx Datum: 07.10.2010 19:06 An: <AUDITORY@xxxxxxxx> Betreff: Re: About importance of &quot;phase&quot; in sound recogni= tion The subject title says "recognition", which is a lot different than "discrimination", but I don't get the sense that recognition is all that people are talking about on this thread. To me, the definitive paper on phase discrimination on steady-state complex tones was by Plomp and Sieeneken in 1969: R. Plomp and H. J. M. Sieeneken, "Effect of phase on timbre of complex=20 tones", J. Acoust. Soc. Am. 46, No. 2 (pt.2), 409-421 (1969). The prototype signal was a sawtooth but with only 10 harmonics in the Fourier series. Phase angles on the harmonics were random multiples of pi/16. The conclusions were: (1) The timbre difference between a tone consisting of only sine or cosine terms and a tone consisting of alternative sine and cosine terms represents the maximal possible effect of phase on timbre; (2) the maximal effect of phase on timbre is quantitatively smaller=20 than the effect of changing the slope of the amplitude pattern by 2 dB/pct and is less for higher than for lower frequencies;=20 (3) the effect of phase on timbre appears to be independent of the=20 effect of amplitude pattern and of the loudness factor. There have been a lot of papers about the importance of phase in musical contexts. Here are a couple: T. H. Andersen and K. Jensen, "Importance and representation of phase in the sinusoidal model" J. Audio Engr. Soc. 52, No. 11, 1157-1169 (2004) S. Dubnov and X. Rodet, "Investigatioi of phase coupling phenomena in sustained portion of musical isntruments sounds", J. Acoust. Soc. Am. 113, No. 1, 348-359 (2003). Jim Beauchamp Univ. of Illinois --------------------------------------------------- Reinhart Frosch, Dr. phil. nat., CH-5200 Brugg. reinifrosch@xxxxxxxx . ------=_Part_1369_17538468.1286530875460 Content-Type: text/html;charset="UTF-8" Content-Transfer-Encoding: quoted-printable <html><head><style type=3D'text/css'> <!-- div.bwmail { background-color:#ffffff; font-family: Trebuchet MS,Arial,Helv= etica; font-size: 12px; margin:0; padding:0;} div.bwmail p { margin:0; padding:0; } div.bwmail table { font-family: Trebuchet MS,Arial,Helvetica; font-size: 12= px; } div.bwmail li { margin:0; padding:0; } --> </style> </head><body><div class=3D'bwmail'><P>Hello James (et al.),</P> <P>I have not yet read Plomp and Sieeneken (1969), but shall do so as soon = as possible. In the meantime, my newest synthesizer experiment may be of so= me interest:</P> <P>In the case of a one-octave two-tone (440 Hz, 880 Hz) composed of two si= nusoidal tones, I hear, both at the onset and later, no dependence of = the loudness and the timbre on the delay (i.e., the phase) between the two = tones, although the waveform of the complete signal does depend on that del= ay. These two sine tones form a harmonic complex tone, and the strengths of= its two partials are delay-independent.<BR>With two harmonic complex tones= (harmonica voice), however, timbre and loudness of the one-octave tw= o-tone vary from one try to the next. The variation is weaker than in the c= ase of two equal frequencies. Constructive and destructive interference amo= ng a part of the harmonics takes place. <BR>The results for a one-just-fift= h two tone (440 Hz, 660 Hz) are similar. The variation of timbre and loudne= ss in the case of harmonic complex tones is now fairly weak, however. <BR>R= einhart. <BR><BR>----Urspr=C3=BCngliche Nachricht----<BR>Von: jwbeauch@xxxxxxxx= RED.MUSIC.UIUC.EDU<BR>Datum: 07.10.2010 19:06<BR>An: <AUDITORY@xxxxxxxx= ILL.CA><BR>Betreff: Re: About importance of &quot;phase&quot; in= sound recognition<BR><BR>The subject title says "recognition", which is a = lot different than<BR>"discrimination", but I don't get the sense that reco= gnition is all<BR>that people are talking about on this thread.<BR><BR>To m= e, the definitive paper on phase discrimination on steady-state<BR>complex = tones was by Plomp and Sieeneken in 1969:<BR><BR>R. Plomp and H. J. M. Siee= neken, "Effect of phase on timbre of complex <BR>tones", J. Acoust. Soc. Am= . 46, No. 2 (pt.2), 409-421 (1969).<BR><BR>The prototype signal was a sawto= oth but with only 10 harmonics in the<BR>Fourier series. Phase angles on th= e harmonics were random multiples<BR>of pi/16. The conclusions were:<BR><BR= >(1) The timbre difference between a tone consisting of only sine or<BR>cos= ine terms and a tone consisting of alternative sine and cosine<BR>terms rep= resents the maximal possible effect of phase on timbre;<BR>(2) the maximal = effect of phase on timbre is quantitatively smaller <BR>than the effect of = changing the slope of the amplitude pattern by<BR>2 dB/pct and is less for = higher than for lower frequencies; <BR>(3) the effect of phase on timbre ap= pears to be independent of the <BR>effect of amplitude pattern and of the l= oudness factor.<BR><BR>There have been a lot of papers about the importance= of phase in<BR>musical contexts. Here are a couple:<BR><BR>T. H. Andersen = and K. Jensen, "Importance and representation of phase<BR>in the sinusoidal= model" J. Audio Engr. Soc. 52, No. 11, 1157-1169 (2004)<BR><BR>S. Dubnov a= nd X. Rodet, "Investigatioi of phase coupling phenomena in<BR>sustained por= tion of musical isntruments sounds", J. Acoust. Soc. Am.<BR>113, No. 1, 348= -359 (2003).<BR><BR>Jim Beauchamp<BR>Univ. of Illinois</P> <P>---------------------------------------------------</P> <P>Reinhart Frosch,<BR>Dr. phil. nat.,<BR>CH-5200 Brugg.<BR>reinifrosch@xxxxxxxx= ewin.ch .<BR><BR><BR></P></div></body></html> ------=_Part_1369_17538468.1286530875460--