DVD-Audio on PC's?

DarkEdgeX asks: "I've been looking, admittedly for a brief period, for a player that will work with DVD-ROM drives to play DVD-Audio discs through a PC (any platform, Win32, Linux, etc). Does such a thing exist, free or otherwise? I know that DVD-Video players can play the audio tracks encoded for Dolby 5.1, but it doesn't get to the better quality sound that's embedded in the AUDIO-TS subdirectory on DVD-Audio, it just reads the VIDEO-TS files. (In fact, from what I've read, DVD-Audio discs often do this for compatibilities sake, otherwise the only directory on a DVD-Audio disc that's really needed is AUDIO-TS.) Finally, are there any *technical* differences between DVD-Audio players and DVD-ROM's in so far as hardware is concerned? (A home DVD-Audio player from Pioneer, retail anyways, goes for $2000-3000!)"

Comments

A couple possible technical differences

[Platinum Dragon]

1) CSS2: Remember the DVD Group/Consortium/Circlejerk popping off about CSS being cracked and having to develop a new algorithm? In this case, it might be just a matter of the accompanying software implementing CSS2, though a circuit change might be necessary within the DVD-ROM itself. I'm not entirely sure on this; there's a specific circuit in DVD-ROM drives to carry CSS info, but it might be just for key exchange data transmission.

2) Bandwidth: I wish I knew where my DVD drive manual was right now, because I don't feel like slogging through Creative's site. DVD-Audio has a higher bandwidth limit than DVD-Video; 9.6 Mb/s as opposed to 6.144 Mb/s. A slightly better laser is necessary (I think; I'm extrapolating from what I know of the format), and the data path coming out of the drive needs to be able to handle 9.6 Mb/s of data coming down the pipe. IDE and SCSI might handle this without sneezing; I'm not going to take completely wild guesses without studying the docs.

3) MLP and SMART: Meridian Lossless Packing is a wunderbar compression scheme that allows for more music to be packed on the disc and through the data stream. A decoder for this is necessary. As well, there's a downmixing scheme called SMART (again, don't ask when I don't have the docs in front of me) that attempts to mix multiple channels into a stereo mix. I'm not sure of anyone actually using this - who wants to trust the computer with your high-end audio mixes? - but it's necessary in DVD-Audio players.

CSS2, MLP and SMART decoding might be possible within software, but it would take a nice high-end chip, or, a dedicated DVD-Audio card with the firmware to handle that decoding. The "normal" DVD-Audio streams are Linear PCM, the same stuff on CDs, only at much higher bitrates, sampling rates, and with multiple channels. As you said, the Dolby 5.1/DTS tracks are there for compatibility. I've heard little to nothing about DVD-Audio-capable DVD-ROMs, simply because it's seen as an audiophile format at this point. Most people get off on two channel stereo CDs.

I find it unfortunate most people my age (around 21) think Mp3 and CD are as good as it gets, and having "theater-quality" sound is left to the theaters and a few insane audiophiles. I'm working with a group on a DVD-Audio project composed of all original music by a series of Canadian groups, and we're all in our early twenties. I've heard DVD-Audio in all its glory, and it's worth the investment in equipment if you're even a borderline audiophile. The competing format SACD is also a worthy option, especially if you want to have discs you can let your non-audiophile friends borrow, although they won't get the superior SACD sound.

Re:A couple possible technical differences

[SuiteSisterMary]

DVD video clocks in at 10 megabits; it's the equivalent of a 9 speed CD-ROM. Given that I've got a 5x DVD-ROM, I don't think DVD-Audio will exceed my IDE bus. All it should take is decoder software.

Re:A couple possible technical differences

[marm]

I find it unfortunate most people my age (around 21) think Mp3 and CD are as good as it gets, and having "theater-quality" sound is left to the theaters and a few insane audiophiles.

This is all very well (and I agree with you that digital audio does get better than CD) but the key thing to remember is that unless you have thousands of dollars worth of other audio equipment and much time invested in making your listening environment acoustically pleasing, the enhanced quality that DVD-Audio and SACD bring is pointless. The wonderfully crisp high-end and reduction in quantization noise gets completely buried in class-A transistor amp mush and funky reverberation modes of the listening room. Thus, until cheap (sub-$1k) audio hardware gets significantly better and your average Joe becomes interested in acoustically reshaping his living room, DVD-Audio and SACD will stay as obscure audiophile formats.

This is to say nothing of the fact that most recording studio equipment is nowhere near the quality required for recording these new formats properly - in a typical studio the best digital audio recorders they have are 20-bit, 48kHz ADATs...

The reason CD succeeded tape and vinyl is because your typical guy could hear the difference, with amplifiers and speakers that they already owned. In the early days of CD very few recordings were done digitally, but a recording done on quarter-inch reel-to-reel tape still sounds an awful lot better mastered onto CD than it does on cassette tape. SACD and DVD-Audio require both better audio hardware than the average guy has and better recording equipment than the average studio has to even begin to notice the difference.

The multi-channels are good though, and if DVD-Audio especially is ever going to make it mainstream, then it should be that which the marketers focus on rather than the quality aspects.

Re:A couple possible technical differences

[Platinum Dragon]

DVD video clocks in at 10 megabits; it's the equivalent of a 9 speed CD-ROM.

I now see where my error came from.

After doing some more digging through specs and FAQs, yes, the DVD-Video max bitrate is 10.08 Mbps. The normal max audio bitrate is 3.1 Mbps. However, there is a non-standard digital PCM audio output available in DVD-Video that can produce 24 bit, 96 kHz, running at - wait for it! - 6.144 Mbps. *That* explains where I got that bitrate from; I originally heard it at a conference on DVD-Audio/SACD in reference to "maximum bitrate;" although I should have known being at an audio conference, it wasn't specified that this referred to audio bitrate only.

Sidenote from the DVD FAQ; the CSS license doesn't allow for digital output of CSS-protected PCM streams at 96 MHz; the player must downsample to 48. The inability to legally get digital PCM audio output at high bitrates was a sore point among the engineers I heard from at said conference. Try to find a DVD-Audio player that will give you digital PCM outputs. Good luck, and get ready to shake your head in disbelief:)

Anyway, yeah, now that I look back over the notes, it should be possible to support DVD-Audio in software using existing DVD-ROM drives. However, it would require at least some software rewrites, and possibly a lot of large rewrites due to the completely different processes a DVD-Audio stream goes through during decoding. There's the need to support the things I mentioned above (CSS2, MLP, SMART, and of course you need to pay licenses for those:), among other things I can't imagine I missed. There isn't any decoding hardware available (that I know of) for DVD-Audio streams like there is for DVD-Video that incorporate the above decoders, so the audio on slow machines (ie; my Pentium II 266) will be just unlistenable.

There are barriers, but quite frankly, they're easily surmounted. There just isn't any large demand right now for DVD-Audio playing on computers, not enough to justify the costs of software and hardware development for the beancounters. Unfortunate, but reality just sucks sometimes.