<div dir="ltr">On Mon, Oct 13, 2008 at 2:16 PM, Steven Ellis <span dir="ltr"><<a href="mailto:steven@openmedia.co.nz">steven@openmedia.co.nz</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div style=""><div><div><div class="Wj3C7c"><div>On 14/10/2008, at 9:51 AM, Nick Rout wrote:</div>On Mon, Oct 13, 2008 at 9:13 PM, Aaron Whitehouse<br><blockquote type="cite"><div><blockquote type="cite">2. Has anyone got 5.1 sound working? Is the way that people are doing<br>
</blockquote><blockquote type="cite">this using S/PDIF over coax/optical? How well does the S/PDIF<br></blockquote><blockquote type="cite">pass-through work with recent distributions?<br></blockquote>Mine has always worked fine.</div>
</blockquote></div></div><div>Same here</div><div class="Ih2E3d"></div></div></div></blockquote><div><br>And me. I'm using coax; PCM, AC3, and DTS all work fine.<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div style=""><div><div><blockquote type="cite"><div>Most guides that I have<br><blockquote type="cite">found are quite old. I assume that the S/PDIF carries a digital signal<br></blockquote><blockquote type="cite">encoded in AC3 or PCM.<br>
</blockquote>by definition I think spdif must be ac3 or pcm</div></blockquote>Or DTS</div><div></div></div></div></blockquote><div><br>Yes.<br><br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div style=""><div><div>Some Amps won't accept anything other than 44.1 and 48KHz PCM which can cause issues with some internet streams, but otherwise no issues.</div><div class="Ih2E3d"></div></div></div></blockquote>
<div class="Ih2E3d"><br>Also, some soundcards won't output one or the other via SPDIF. Hopefully this is fairly uncommon these days but it may pay to read the small print.<br> <br><blockquote type="cite"><div>Is there some negotiation between the card and<br>
<blockquote type="cite">the computer that lets the computer figure out which formats it can<br></blockquote><blockquote type="cite">pass-through and which have to be re-encoded into formats that the<br></blockquote><blockquote type="cite">
stereo etc. can support? Do you set all of that manually?<br></blockquote>I think myth does it all in software, it passes ac3 and pcm streams<br>through. other codecs it presumably converts to pcm (as it would have<br>to do for analogue output anyway). Most decent digital input<br>
amplifiers will mix sound so it comes out all speakers.<br><br></div></blockquote><div>There's no negotiation, and for PCM MythTV doesn't know anything about the process. If your soundcard is configured to output to SPDIF then it'll send all PCM data (that's in the right format - generally 16bit 44.1 or 48kHz stereo) to that output. Usually with ALSA these days no configuration is needed, you just need to set your output device to the right one.<br>
<br>For AC3 and DTS you need to tell MythTV to pass these through otherwise Myth will decode them to stereo.<br></div></div></div><br>Cheers,<br>Steve<br></div>