24/96 question

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Okay, here's a simple question, I've seen information in this forum about 24 bit/96KHz capable DACs, what I want to know is, can these be used to decode a 24/96 output from a DVD player? I have at least one DVD that has 24/96 track and am curious if I use one of those DACs, could it actually decode the information and convert it to analog or is there something more that needs to be done? (I don't have a digital receiver yet, and am just curious if this could be done) Thanks for the info!
If you have a 24/96 track then a 24/96 DAC will decode it. But your DVD Player must have a 24/96 output. You see some DVD players down mix a 24/96 track to about 24/48 (maybe 16/48) before outputing it. Why? Well because the so called copy right protection laws invented probably by the same idiots who came up with the zone system demand this.

There are a couple of players which will output 24/96 - Pioneer Players do I think.

This reminds me - has a format for 24/192 or DSD been established yet?
Hello there!
You where talking about a DVD. Most DVDs use Dolby Digital (AC-3) sound track, which is MPEG-1 Layer 2 compressed sound. You have no use for a DAC in that case. It outputs only noice. Ok, if you put a AC-3 decoder inbetween it should work, but stand-alone decoders are expensive. I don't know if some music-DVDs use regular pcm-sound (like CD-tracks)(?). It is not standardized. And if you play regular music-CDs there you have only 44 kHz/16 bit.
I'm well aware that most DVDs are DD or DTS, but what I am refering to are DVDs that have a 24/96 PCM track on them. In particular my wife's copy of "Into the Woods" was recorded this way, and the ELP "Brain Salad Surgery" also has a 24/96 encoded track on it as well. Its mostly a curiosity and mostly moot now, as I think I'm going to be buying a digital receiver either this month or next.
Sounds interesting. I didn't know that there where such DVDs on the market, though it is technically possible. It should also be possible to make your own 24/96 DVDs with a DVD-burner (DVD+RW is recommended). Most Philips DVD-players' (I own a Philips DVD-751) specification states 24 bit and 96 kHz. But I wonder what you see if you connect an oscilloscope. Ok, the 24 bit should work as it should, but usually the noise floor come against before you reach the theoretical limit, either in the DVD-player itself or in the rest of the audio chain. But there is no guarantee with a 96 kHz system what kind of sound there is above what you can actually hear. But to come to the conclusion, my opinion is that it should work with PCM 24/96.
In response to AudioFreak's comment about down-conversion from the player, the one that I have (Panasonic RV30) has an option to either down-convert or run bitstream out of the digital connection. So all I have to do is set it to bitstream and it'll send it on.

Johan, the 24/96 DVDs are a scarce creature indeed. The one that I have is a live broadway recording that they decided to pump the video bitrate high and use 24/96 instead of digital surround. (What's the point with a live show anyway? Who cares if the person coughing is coming from behind you or in front of you?) The other one I mentioned is a high-brid DVD-audio disc with DD tracks for standard DVD players. (In that case the 24/96 track may only be on the DVD-audio portion, but I won't know until I get the disc) I'll know more about the sound quality/difference in (hopefully) a month, after I get the new receiver.
Hmm, remains to see yet if these old DVD-Video players understand PCM sound on a DVD, I have not tried... They maybe have to be DVD-Audio certified. I know it is possible to burn a regular audio CD but instead of PCM-tracks put Dolby Digital 5.1 tracks. The player plays it like PCM audio and it requires a DD receiver to decode the 5.1 channels. The analog output from the player just outputs noise (dangerous for amplifier/speakers). Would be fun to test a non-standard audio-CD with 24 bit/96kHz PCM stereo and see if the DVD-player likes it and if the receiver understands the PCM audio (and first if some software allows to burn such audio tracks). I have to try it some day.
Quite a jungle with these audio standards. I have to tell (it doesn't belong to this subject) about that I managed to make a standard SuperVideoCD with MPEG-2 multichannel 5.1 audio (the only way to get true multichannel audio for SVCD). But no digital receiver understands MPEG-2 encoded audio (quite funny because MPEG-2 was the audio format first specified for DVD-Video although Dolby Digital and DTS won the battle), though DVD-players usually are able to decode the MPEG audio tracks and put them out from the analog 5.1 output on the player.
I thought mpeg-2 audio was supposed to be the DVD audio standard in Europe? (I take it from your comments, its not) As to the PCM thing, the "Into the Woods" DVD is a full video DVD where they recorded the audio tracks at 24/96 for playback, so the player understands that. (Its the only audio track on the disc in English if I remember correctly)

On a side note, how would you get 24/96 data playback on a standard CD to work? The throughput isn't high enough without some form of compression. (I know about the DTS CDs, I haven't seen a DD CD yet)

As to belonging to this subject, I think we've wandered away from the original question already... (Not that I mind, its still quite interesting!)
I don't know all of the history about DVD, but the fact is that in Europe it is almost only DD (AC-3) DVDs today (a few with DTS). Almost every DVD-player has support for MPEG because of VCD and SVCD compatibility (VCD uses MPEG-1 layer 2 and SVCD may use MPEG-1 stereo, MPEG-2 stereo or multichannel and one or two language tracks).

Another interesting thing is that the European digital cable television standard has MPEG-2 audio. For now at least in Finland they are using only MPEG-2 stereo sound, but they are investigating in using Dolby Digital 5.1. I know also that German and the biggest company in USA has decided to use the same digital cable standard as in Finland. There are lot of work changing to DD, so why they don't use MPEG-2 multichannel? Maybe because of that digital receivers don't support MPEG-2 multichannel.

Ok, I know that IF 24/96 audio works on a CD (absolutely not in any ordinary CD-player) there is room for only about 22 min. of audio (on a 74 min. CD) (see this thread: http://www.diyaudio.com/forums/showthread.php?threadid=123 )

Dolby Digital and DTS CDs should work in exactly the same way.
DVD-audio (24/96 and 24/192) are only now just starting to hit the market. My company's latest DVD system-on-chip, the ZiVA-5, is our first DVD-A capable product, and it has only recently starting going into mass production with our customers. So, it will take some time for the new (but long-promised) standard to work it's way into the marketplace.

If i were you, I'd be looking to do a 24/192 DAC instead of just a 24/96, since it appears now that a good deal of DVD-A content will be released in that format.

As far as the other audio standards go, MPEG-2 audio is pretty much the standard audio format for DVD movies in Europe, while in North America, AC-3 encoding is generally used.
Any statements made here do not reflect the opinion of my employer, LSI Logic Corp.
Thanks for the info about 24/192. I'll keep that in mind.

But I don't agree that MPEG-2 should be very common in Europe. Every DVD but one that stands on my shelf at home has Dolby Digital (AC-3) audio. I've got only one with MPEG audio. The problem is that in Europe all digital receivers (amplifiers/decoders) that are sold has support for only DD (AC-3) and DTS. When playing MPEG audio the DVD-player has to have an internal decoder with analog output (but I have never seen any DVD so far with MPEG-2 5.1 audio, only stereo).

I had the misapprehension(?) that DTS was common in north America. Only a few DVDs here in northern Europe has DTS.
oops - i made a boo-boo. I had a second look at the ZiVA specs today and noticed that at present we are only officially supporting 96kHz output for SPDIF. There is a chance that we will be supporting 192kHz in the future. Sorry to jump the gun on that one fellas... ;)

In any case, 192 is definitely a part of the DVD-A standard, though 96kHz and 88.2kHz were only recently adopted as part of the IEC-958 specification (and have content limitations imposed by DVD-Audio and DVD-Video standards). It remains to be seen if 192 will be fully embraced as part of the IEC-958 interface standard as well... There aren't any 192 receiver chips available yet (at least none that I'm aware of), but the DACs and digital filters are certainly there. As a simple contingency, I don't think it would be a big deal to use 192-capable parts or 96 parts which have traditionally been made pin-compatible with their earlier counterparts.

One trend I am noticing is a shift towards more generalized digital interfaces between consumer electronics. Most prominently of course is IEEE-1394 firewire, and i think we'll see more of this in the future. From the content providers' standpoint, it is a more beneficial interface, since it allows more flexibility with regard to copy protection and encryption. At this point, i don't think firewire has gained enough of a foothold in the market to displace SPDIF for digital audio.

Any statements made here do not reflect the opinion of my employer, LSI Logic Corp.
IEEE 1394

...with great difficulty, i'm afraid. The Firewire interface includes a good deal of encryption and copy protection measures. In addition to that, it's a rather complex interface. Firewire is, in fact, a network interface - there are packets with addresses and priorities, and different possible logical interfaces which can be created between devices connected to the 1394 network: isochronous / asynchronous.

To use firewire, you'll need a PHY layer device such as the TI TSB41LV03, and an LLC (link layer controller). The LLC will interface with your microprocessor, probably using a DMA style interface. Then, you'll need to write some application code to handle the interface. The list of things to deal with just goes on...

So, all in all, I'd say that firewire is a little bit complicated for DIYers at this point. Hopefully at some point a company will release a simple to use firewire system-on-chip like the FT8U245 series USB chips (perhaps there already is one?).
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