a silly question about dvd-a [Archive] - Audio & Video Forums

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ronning
07-20-2004, 08:29 PM
Although very interested in hi-resolution media formats (I own and listen to SACD's) I have not tested out DVD-A much nor do I know all about the format.

I know that DVD-A supports up to 24/192 resolution and also up to 5.1 multichannel sound. I am curious.. can it do both at the same time?

My main question(s), however, have to do with the interface with the digital receiver. Most newer digital receivers have 192/24 DACS on all 6 channels (the Yamaha I'm considering does). Obviously this is for DD/DTS decoding. However, does this also mean it is capable of DVD-A? Or is that a standard all of it's own (and thus requiring a proprietary decoding chip)?

Can any of the DVD-A information be sent digitally to the receiver either via optical or coax, or is it an analog-or-nothing situation? It seems that at the very least a 24/192 stereo DVD-A should be able to output the two 24/192 digital signals via optical/coax to the receiver which the receiver then decodes.

This brings me to another related question regarding DVD players. If the player says it has only 24/96 DAC's, does that mean it cannot relay 24/192 digital audio to the receiver, or does it just mean that the best ANALOG signal it will output will be from 24/96 decoding?

Phew... I guess that's all for now.

I much appreciate any answers.

THanks!

-ronning

Woochifer
07-20-2004, 09:28 PM
Think you got a few things that need to be set straight.

First off, DVD-A is a 192/24 resolution format for two-channel (it's actually a compressed signal, but the MLP protocol adds back discarded bits when the signal is reassembled during playback). With 5.1 playback, the resolution is 96/24 for each channel.

The 192/24 DACs in that receiver will make absolutely no difference because there are no unencrypted 192/24 discs out there for consumers to use. Unless you use professional equipment or a soundcard with unencrypted high res datastreams, you won't ever use that resolution. It looks good on marketing pieces, and the 192/24 DACs are what get mass produced nowadays, so going with them doesn't cost anymore than the run-of-the-mill 96/24 chips.

DVD-A has the resolution, but it's encrypted for copy protection and can only be played back through the analog outputs. It cannot output a 192/24 digital signal or even a 96/24 signal, only analog. DD and DTS will not make use of that resolution either because neither of them are true 24-bit formats.

The only unencrypted high res discs out there for consumers that can be output directly to a receiver digitally are the uncompressed 96/24 PCM audio tracks that come with some DVD video discs, and the video-compatible layer on a few DVD-A discs (which normally contain a 5.1 DD or DTS track). Classic Records makes these and the ones that I've bought sound uniformly excellent. Chesky also makes them. They take up a lot of space, so they do not provide moving pictures. Keep in mind that for copy protection, some of them are downsampled to 48/24 resolution before they get output digitally, and some DVD players do this downsampling by default.

ronning
07-20-2004, 10:40 PM
Think you got a few things that need to be set straight.

First off, DVD-A is a 192/24 resolution format for two-channel (it's actually a compressed signal, but the MLP protocol adds back discarded bits when the signal is reassembled during playback). With 5.1 playback, the resolution is 96/24 for each channel.

The 192/24 DACs in that receiver will make absolutely no difference because there are no unencrypted 192/24 discs out there for consumers to use. Unless you use professional equipment or a soundcard with unencrypted high res datastreams, you won't ever use that resolution. It looks good on marketing pieces, and the 192/24 DACs are what get mass produced nowadays, so going with them doesn't cost anymore than the run-of-the-mill 96/24 chips.

DVD-A has the resolution, but it's encrypted for copy protection and can only be played back through the analog outputs. It cannot output a 192/24 digital signal or even a 96/24 signal, only analog. DD and DTS will not make use of that resolution either because neither of them are true 24-bit formats.

The only unencrypted high res discs out there for consumers that can be output directly to a receiver digitally are the uncompressed 96/24 PCM audio tracks that come with some DVD video discs, and the video-compatible layer on a few DVD-A discs (which normally contain a 5.1 DD or DTS track). Classic Records makes these and the ones that I've bought sound uniformly excellent. Chesky also makes them. They take up a lot of space, so they do not provide moving pictures. Keep in mind that for copy protection, some of them are downsampled to 48/24 resolution before they get output digitally, and some DVD players do this downsampling by default.

Thank you. Much of this is as I expected, I just wanted to make sure.

It all leads up, of course, to the a question regarding a particular DVD player I'm looking at (also see my other post: "reconsidering") the Samsung DVD-HD841. It claims to be a DVD-A player but only has 96khz DACS. What does this mean?

Thanks