A small update (but not a lot to add)... I've bought an Edirol UA-1D, which basically gives me S/PDIF input/output (both co-ax and optical) on my laptop. I probably need to learn more about how to use it as some tests on my DVD player's output failed to yield a recording, but I did manage some minor verifications:
The 48KHz WAV files I've generated containing DTS data played back fine over the S/PDIF line, at the correct speed. My suspicion was that 'Bug#128' (http://bugs.slimdevices.com/show_bug.cgi?id=128) was responsible for the slowed-down audio, but until now I've not been able to be absolutely sure that the file itself wasn't somehow causing it. I tried to record the output of the SB2 playing back a DTS-FLAC file, but the recording didn't work. I was using Audacity, and the time indicator in the recording stream seemed to get stuck... I don't know if a better free app is available for this sort of thing, but will look into it at some point. Since DTS-FLAC playback through my receiver sounds jerky, I suspect that the recording problem was down to a bad stream (but I'm hand-waving when I write that... figuratively). I successfully recorded the output of the SB2 playing back a DTS-WAV file, and most of the data is bit-perfect... but there's the odd anomaly which I don't understand. (A 0x01 near the start of one frame has been changed to 0x02; some 0x0Ds have been changed to 0x0D0A! Maybe the bytes involved are a coincidence, but the latter looks like a newline fixup.) But I don't know whether the changes come from the SB2, the S/PDIF->USB converter, Audacity... I just don't know enough about the pipeline at this time. Of course, the DTS-WAV files sound fine to me through the receiver so this might point to the post-SB2 stages of the pipeline being at fault when recording to the laptop (it's quite likely given that this aspect is all new to me)... but then, maybe the differences wouldn't be audible to me. I reckon my code (for generating these files) is as complete as it'll get, and need only to be sure about the licence before I post it here. I'm happy for it to be public-domain, but I have used a 3-value lookup table from another project -- if I can find the reference material for that table it's no problem, but otherwise I'm not sure if the use of it has an effect on the licence. Cheers, Steve -- smst ------------------------------------------------------------------------ smst's Profile: http://forums.slimdevices.com/member.php?userid=752 View this thread: http://forums.slimdevices.com/showthread.php?t=15271 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
