Re: Sound head of the 'Moviola' (James Johnston )


Subject: Re: Sound head of the 'Moviola'
From:    James Johnston  <James.Johnston@xxxxxxxx>
Date:    Wed, 29 Dec 2010 13:47:27 -0800
List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>

--_000_A3A915D4968D3547B15269C244643B620AFB8F217EEXCHANGE2K7dt_ Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" There is no need for "quantization". Frequency and phase are the Fourier Transform (which is a linear, energy-pr= eserving transform) of Amplitude in the time domain. The Fourier Transform is really a complex, but it often gets converted to p= olar. More convenient sometimes, less so sometimes. ________________________________ From: AUDITORY - Research in Auditory Perception [AUDITORY@xxxxxxxx= On Behalf Of Kevin Austin [kevin.austin@xxxxxxxx Sent: Wednesday, December 29, 2010 1:29 PM To: AUDITORY@xxxxxxxx Subject: Re: [AUDITORY] Sound head of the 'Moviola' In the time domain, as Hugh Le Caine used to say, everything is amplitude (= displacement). As I understand this, frequency and phase are derived from a= mplitude in [quantized] time. Kevin On 2010, Dec 29, at 2:47 AM, ita katz wrote: But the amplitude does not carry all the information needed to recreate the= sound. Similarly, the "Sound-on-Film" entry states: stereo variable-area<http://en.wikipedia.org/w/index.php?title=3DStereo_var= iable-area&action=3Dedit&redlink=3D1> (SVA) recording, encoding a two-chann= el audio signal as a pair of lines running parallel with the film's directi= on of travel through the projector. The lines change area (grow broader or = narrower) depending on the magnitude of the signal. Again, what encodes the frequency/phase? Thank you Ita. Notice: This message and any included attachments are intended only for the use of = the addressee, and may contain information that is privileged or confidenti= al. If you are not the intended recipient, you are hereby notified that any= dissemination, distribution or copying of this communication is strictly p= rohibited. If you have received this communication in error, please destroy= the original message and any copies or printouts hereof. --_000_A3A915D4968D3547B15269C244643B620AFB8F217EEXCHANGE2K7dt_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="iso-8859-1" <html dir=3D"ltr"><head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Diso-8859-= 1"> <meta name=3D"GENERATOR" content=3D"MSHTML 8.00.6001.18999"> <style id=3D"owaTempEditStyle"></style><style title=3D"owaParaStyle"><!--P { MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px } --></style> </head> <body ocsi=3D"x"> <div style=3D"FONT-FAMILY: Tahoma; DIRECTION: ltr; COLOR: #000000; FONT-SIZ= E: 13px"> <div>There is no need for &quot;quantization&quot;.</div> <div><font size=3D"2" face=3D"tahoma"></font>&nbsp;</div> <div><font size=3D"2" face=3D"tahoma">Frequency and phase are the Fourier T= ransform (which is a linear, energy-preserving transform) of Amplitude in t= he time domain.</font></div> <div><font size=3D"2" face=3D"tahoma"></font>&nbsp;</div> <div><font size=3D"2" face=3D"tahoma">The Fourier Transform is really a com= plex, but it often gets converted to polar. More convenient sometimes, less= so sometimes.</font></div> <div dir=3D"ltr"><font color=3D"#000000" size=3D"2" face=3D"Tahoma"></font>= &nbsp;</div> <div style=3D"DIRECTION: ltr" id=3D"divRpF27922"> <hr tabindex=3D"-1"> <font color=3D"#000000" size=3D"2" face=3D"Tahoma"><b>From:</b> AUDITORY - = Research in Auditory Perception [AUDITORY@xxxxxxxx On Behalf Of Kev= in Austin [kevin.austin@xxxxxxxx<br> <b>Sent:</b> Wednesday, December 29, 2010 1:29 PM<br> <b>To:</b> AUDITORY@xxxxxxxx<br> <b>Subject:</b> Re: [AUDITORY] Sound head of the 'Moviola'<br> </font><br> </div> <div></div> <div> <div><br> </div> <div>In the time domain, as Hugh Le Caine used to say, everything is amplit= ude (displacement). As I understand this, frequency and phase are derived f= rom amplitude in [quantized] time.</div> <div><br> </div> <div>Kevin</div> <div><br> </div> <div><br> </div> <div><br> </div> <br> <div> <div>On 2010, Dec 29, at 2:47 AM, ita katz wrote:</div> <br class=3D"Apple-interchange-newline"> <blockquote type=3D"cite"> <div dir=3D"ltr"> <div>But the amplitude does not carry all the information needed to recreat= e the sound. Similarly, the &quot;Sound-on-Film&quot; entry states:<br> <br> <blockquote style=3D"BORDER-LEFT: rgb(204,204,204) 1px solid; MARGIN: 0pt 0= pt 0pt 0.8ex; PADDING-LEFT: 1ex" class=3D"gmail_quote"> <a class=3D"new" title=3D"Stereo variable-area (page does not exist)" href= =3D"http://en.wikipedia.org/w/index.php?title=3DStereo_variable-area&amp;ac= tion=3Dedit&amp;redlink=3D1" target=3D"_blank">stereo variable-area</a> (SV= A) recording, encoding a two-channel audio signal as a pair of lines running parallel with the film's direction of travel through= the projector. The lines change area (grow broader or narrower) depending = on the magnitude of the signal.</blockquote> <div><br> Again, what encodes the frequency/phase?<br> <br> Thank you<br> <br> Ita.</div> </div> </div> </blockquote> <div><br> </div> <div><br> </div> <div><br> </div> </div> </div> </div> <DIV> Notice:<BR> This message and any included attachments are intended only for the use of = the addressee, and may contain information that is privileged or confidenti= al. If you are not the intended recipient, you are hereby notified that any= dissemination, distribution or copying of this communication is strictly p= rohibited. If you have received this communication in error, please destroy= the original message and any copies or printouts hereof.<BR> </DIV></body> </html> --_000_A3A915D4968D3547B15269C244643B620AFB8F217EEXCHANGE2K7dt_--


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