Clemens Ladisch <[EMAIL PROTECTED]> writes: >> > Does it work if you play a stereo PCM stream to hw:0,2? >> >> Yes. >> >> A DTS stream also works (although my amplifier recognizes it as a DTS >> stream from a CD audio, not from a DVD). > > That's strange, there should be no difference between DTS and AC3 as > far as the sound card is concerned.
Yes. Moreover, the DTS stream is detected as coming from a CD (albeit at 48Khz, go figure). That makes me wonder how a yamaha amplifier (DSP A1) is able to detect whether a DTS stream is coming from a CD or a DVD. I guess that some flag is present is the DTS from DVD stream that is missing (unset) in the DTS from CD stream. I (also) guess that this flag is mandatory for AC3 stream that can only come from DVD (well, that's the point of view of my amplifier). I guess (again) that the stream from my nforce board does not set this mysterious flag. So only PCM and DTS (seen as coming from a CD) is working. AC3 without this flag is rejected by my amplifier (this would explain why I sometimes hear a very short scratchy (may be a short lived white noise) when I start to play the AC3 stream from ac3dec. That's a lot of guesswork.... I'll try to find some data regarding DTS in SPDIF encapsulation. AFAIR, the DTS on CD is a hack and a CD player is tricked into believing that DTS is regular audio. The DVD forum did not accept this hack and required a specific flag that was later introduced in DVD player. That's why early DVD player are not DTS compatible. HTH ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ Alsa-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-user
