Re: DVD-A Semantics

sukothai said:

This DVD FAQ page says that while every DVD player is required to support LPCM, they are not required to output every channel discretely.

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Where can I find this statement in the (at least partially outdated) document? What should it mean? Some channels are discrete and what happens to the other channels? Matrixed?

It says most DVD players convert the LPCM to Dolby Surround, Dolby PLII or Dolby Digital for output to a receiver.

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This seems to be nonsense to me because these DVD players would need the appropriate encoders and the necessary processing power for real time encoding. Again: Where can I find this statement in the linked document?

The players are required to have an AC3 decoder. From what I read it looked like the discrete channels were sent out the digital coax or optical output. If only stereo, then they are mixed down to Dolby Surround.

It's not nonsense - it is what my Pioneer players are doing.

sukothai said:

The players are required to have an AC3 decoder.

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Right, but not an AC3 encoder.
If you have PCM and want to output AC3, you need an AC3 encoder. Without an AC3 encoder you can output AC3 only, if there is AC3 anyway on your disc.

From what I read it looked like the discrete channels were sent out the digital coax or optical output.

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If it is LPCM, as you wrote in your prior post, this can only be stereo and not multi-channel.

If only stereo, then they are mixed down to Dolby Surround.

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Why should this happen? There is absolutely no reason for doing this.

It's not nonsense - it is what my Pioneer players are doing.

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I doubt it. What models?

Why don't you answer my questions: Where can I find a proof of your statements

This DVD FAQ page says that while every DVD player is required to support LPCM, they are not required to output every channel discretely.

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and

It says most DVD players convert the LPCM to Dolby Surround, Dolby PLII or Dolby Digital for output to a receiver.

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?

I was excited about your claim and in theory you are correct: the spec says you can do up to 8 channels in 16/48 LPCM or 6 channels in 20/48 LPCM. The problem is, my Pioneer DV-48AV, my Pioneer DV-58AV and Pioneer AVH-P7800DVD all mix the LPCM channels down to stereo. I assume it is Dolby Surround because in the audio part of section 3.2 of the DVD FAQ it says:

"Any disc with multichannel audio is automatically decoded and downmixed to 2-channel Dolby Surround output for connection to a regular stereo system or a Dolby Surround/Pro Logic system."

I assume it is mixed down to Dolby Surround because I can hear all of the channels, but they are only coming out of the front stereo speakers. The Pioneer players are all DVD-Audio players; so they have the capability to output discrete LPCM, but Pioneer chose not to do it. However, my goto player, the Oppo BDP-95, plays a 6 channel 16/48 LPCM DVD-V disc discretely out of all 6 channels. So, my excitement ended when I realized the player support is spotty and I won't be able to use the technology to play discs in my car.

My other issue is tools. To use this technology, you need tools that support it. The tools I found were limited to 16 or 24 bit and 2, 6 or 8 channels. That limits your options with a maximum bit rate of 6.144 Mbps.

That's where I'm at. If you can specify some car DVD-V players that support 24/48 LPCM with 5 channels (my minimum to be acceptable) and tools I can use to make the discs, then I will be interested in continuing this conversation. Otherwise, I'm done looking at DVD-V LPCM as a possible lossless option.

sukothai said:

... The problem is, my Pioneer DV-48AV, ...

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This player doesn't have a HDMI connector, so you have to use SPDIF and SPDIF can't output multichannel PCM, only stereo PCM.

... my Pioneer DV-58AV ...

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Is it connected via HDMI to the receiver/amplifier?

... Pioneer AVH-P7800DVD ...

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I don't know this player.

... all mix the LPCM channels down to stereo...

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The DV-48AV has no other choice.
For the DV-58AV something is wrong in your settings either in the player or in the receiver/amplifier or both.

... I assume it is Dolby Surround because in the audio part of section 3.2 of the DVD FAQ it says:

"Any disc with multichannel audio is automatically decoded and downmixed to 2-channel Dolby Surround output for connection to a regular stereo system or a Dolby Surround/Pro Logic system."

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But this sentence relates to analog audio. We are talking all along about PCM, which is digital.

... The Pioneer players are all DVD-Audio players; so they have the capability to output discrete LPCM, but Pioneer chose not to do it...

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At least the DV-48AV can not output multi-channel LPCM, only stereo LPCM because of the SPDIF connection to the receiver/amplifier. The DV-58AV should do it.

Conclusion:
You can't find a proof for your claims in the document.

These are all DVD-Audio players and all play 6 channel DVD-Audio just fine. They are hooked up properly to do so. Please just accept the fact that this is not viable.

I'm not interested in finding proof in a spec or a document. Find me an automobile player that plays 5 channel 24/48 LPCM DVD-V discs and I will be interested again.

sukothai said:

... I'm not interested in finding proof in a spec or a document...

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See:

sukothai said:

This DVD FAQ page says that while every DVD player is required to support LPCM, they are not required to output every channel discretely. It says most DVD players convert the LPCM to Dolby Surround, Dolby PLII or Dolby Digital for output to a receiver...

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I'm sorry you took that as a challenge. That reference was my attempt to find an explanation for what I was experiencing on actual devices. I would be happy to put a sample ISO file up somewhere so other people can try this out. I would love to find an automobile player that supports this format.