Re: surround sound tech info? (Eero Aro )


Subject: Re: surround sound tech info?
From:    Eero Aro  <arox(at)SAUNALAHTI.FI>
Date:    Fri, 2 Apr 2004 00:05:35 +0300

--=====================_9938436==_.ALT Content-Type: text/plain; charset="iso-8859-1"; format=flowed Content-Transfer-Encoding: quoted-printable Hermann Stemberger replied to Jim Stevenson: >There are many types of Surround: Dolby Stereo (Analog, mono-surround >channel), Dolby Surround (Analog - also called "Pro Logic") Just to clarify; Dolby Stereo and Dolby Surround are two different names for the same encoding. Dolby Stereo was designed for the movie industry and uses Dolby A or SR noise reduction, whereas Dolby Surround was targeted to domestic applications and has no noise reduction (except internally). >switching between stereo on surround will always >be noticed because you're "switching on" (at least) one Surround-channel >(from the back!). As a matter of fact switching _off_ the surround channels is more easily detected, provided that the surround mix was properly done. "Switching on" shouldn't be too detectable. >There are different socalled "upmix" (=3Dmake e.g. 5.1 channels out of 2) >algorhythms available. The most known is the (already mentioned) Dolby >Pro Logic Encoder. Dolby Pro Logic only applies to _decoding_ a Dolby Stereo/Surround signal. A Dolby Stereo/Surround encoder was designed to encode four channels of audio into two channels. Yes, you can consider Dolby Stereo encoding as an upmix algorhythm, but originally it is just an encoding algorhythm. >As far as i know there is just one professional headphone surround >system from STUDER that is in development stage. That would be the BRS (Binaural Room Simulation) system, now developed by IRT - Institut f=FCr Rundfunktechnik in Munich. More info at www.irt.de The Dolby Headphone was originally developed by Lake DSP, and many of the original forms of it and the hardware used is very professional. The two mailing lists mentioned are probably the best sources for= information about surround sound. Here's one more discussion group, which deals a lot with practical things: http://www.musicplayer.com/ubb/ultimatebb.php?ubb=3Dforum;f=3D16 Eero Aro sound designer arox(at)saunalahti.fi --=====================_9938436==_.ALT Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <html> Hermann Stemberger replied to Jim Stevenson:<br> <blockquote type=3Dcite cite>There are many types of Surround: Dolby Stereo (Analog, mono-surround<br> channel), Dolby Surround (Analog - also called &quot;Pro Logic&quot;)</blockquote><br> Just to clarify; Dolby Stereo and Dolby Surround are two different names<br> for the same encoding. Dolby Stereo was designed for the movie industry and<br> uses Dolby A or SR noise reduction, whereas Dolby Surround was targeted<br> to domestic applications and has no noise reduction (except internally).<br> <br> <blockquote type=3Dcite cite>switching between stereo on surround will always<br> be noticed because you're &quot;switching on&quot; (at least) one Surround-channel<br> (from the back!).</blockquote><br> As a matter of fact switching _off_ the surround channels is more easily<br> detected, provided that the surround mix was properly done. &quot;Switching on&quot;<br> shouldn't be too detectable.<br> <br> <blockquote type=3Dcite cite>There are different socalled &quot;upmix&quot; (=3Dmake e.g. 5.1 channels out of 2)<br> algorhythms available. The most known is the (already mentioned) Dolby<br> Pro Logic Encoder.</blockquote><br> Dolby Pro Logic only applies to _decoding_ a Dolby Stereo/Surround signal.<br> A Dolby Stereo/Surround encoder was designed to encode four=20 channels<br> of audio into two channels. Yes, you can consider Dolby Stereo encoding as<br> an upmix algorhythm, but originally it is just an encoding algorhythm.<br> <br> <blockquote type=3Dcite cite>As far as i know there is just one professional headphone surround<br> system from STUDER that is in development stage.</blockquote><br> That would be the BRS (Binaural Room Simulation) system, now developed<br> by IRT - Institut f=FCr Rundfunktechnik in Munich. More info at <a href=3D"http://www.irt.de/" eudora=3D"autourl"><font= color=3D"#0000FF"><u>www.irt.de<br> <br> </a></font></u>The Dolby Headphone was originally developed by Lake DSP, and many of<br> the original forms of it and the hardware used is very=20 professional.<br> <br> The two mailing lists mentioned are probably the best sources for information<br> about surround sound. Here's one more discussion group, which deals a lot<br> with practical things:<br> <a href=3D"http://www.musicplayer.com/ubb/ultimatebb.php?ubb=3Dforum;f=3D16"= eudora=3D"autourl">http://www.musicplayer.com/ubb/ultimatebb.php?ubb=3Dforu= m;f=3D16</a><br> <br> Eero Aro<br> sound designer<br> arox(at)saunalahti.fi</html> --=====================_9938436==_.ALT--


This message came from the mail archive
http://www.auditory.org/postings/2004/
maintained by:
DAn Ellis <dpwe@ee.columbia.edu>
Electrical Engineering Dept., Columbia University