Matrix encoded CDs have any digital flags???

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gene_stl

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CDs have digital flags, to indicate the presence of absence, of pre emphasis. There are also digital flags, to tell players that can detect them, that a file is MQA or HDCD, which also means, they are not officially compact disc.
I think this may also exist for some other later "20 bit" formats too. They may be backward compatible with regular CD, but probably aren't supposed to use the logo.

My question is, have any of the folks that encoded various quad matrix formats,(onto what are otherwise stereo Compact Discs) figured out a way to (digitally) tell the decoder or player that the file or disc is so encoded?? Or is the only indication the labeling on the jewel case and disc itself? I think the answer is no, but if there is a different answer, I am sure someone here would know about it.
 
The answer is no.
The Quad flag was designed for a discrete 4ch digital stream, but pratically never implemented. Any matrixed quad is a stereo stream, no more.
 
CDs have digital flags, to indicate the presence of absence, of pre emphasis. There are also digital flags, to tell players that can detect them, that a file is MQA or HDCD, which also means, they are not officially compact disc.
I think this may also exist for some other later "20 bit" formats too. They may be backward compatible with regular CD, but probably aren't supposed to use the logo.

My question is, have any of the folks that encoded various quad matrix formats,(onto what are otherwise stereo Compact Discs) figured out a way to (digitally) tell the decoder or player that the file or disc is so encoded?? Or is the only indication the labeling on the jewel case and disc itself? I think the answer is no, but if there is a different answer, I am sure someone here would know about it.
Can't see that ever happening. Why flag something, and that's even if those involved know what a quad matrix system is, when they are officially dead format, with no chance of the required digital decoder ever being available.

Afraid the idea is yet another 🦤
 
For it to be of any real use the player would have to have a built in decoder that would be turned on by the flag. As others have said originally there was a flag to indicate discrete quad but it was never implemented and eventually dropped from the standard.

Missed opportunity, we could've had discrete quad CD's back in the eighties!
 
For it to be of any real use the player would have to have a built in decoder that would be turned on by the flag. As others have said originally there was a flag to indicate discrete quad but it was never implemented and eventually dropped from the standard.

Missed opportunity, we could've had discrete quad CD's back in the eighties!
Afraid, all is not rosey in the technical garden though. It had one serious limitation, maximum playing time of a little over half an hour.
 
It's probably easier to place lossy DTS quad encoded audio (muxed into the .wav container) onto a CD.
I could imagine one of the reasons the humble DTS-CD never really caught on is because of the general public.
Play a DTS-CD without it being connected to a DTS decoder and you'll be presented with loud white noise. Can you imagine the level of returns there would have been?
No matter which way you look at the idea of putting quad onto the silver disc, there's always drawbacks, which explains why we are in the mess today with SACD, Video-DTS and now Bluray.
 
I could imagine one of the reasons the humble DTS-CD never really caught on is because of the general public.
Play a DTS-CD without it being connected to a DTS decoder and you'll be presented with loud white noise. Can you imagine the level of returns there would have been?
Given DTS-CD's were launched more than 25 years ago I wonder if there's some data regarding early returns?!
 
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Afraid, all is not rosey in the technical garden though. It had one serious limitation, maximum playing time of a little over half an hour.
Longer playing time than that! Look at all the 2frs out there. Normally two (stereo) albums fit on one CD. Most quads would fit but likely with no room for bonus tracks. Worst case you would need two discs.

I always thought that the CD should have been made a bit larger, perhaps 7". A moot point now with more modern technology like Blu-ray, playing time is not a problem!
 
I could imagine one of the reasons the humble DTS-CD never really caught on is because of the general public.
Play a DTS-CD without it being connected to a DTS decoder and you'll be presented with loud white noise. Can you imagine the level of returns there would have been?
No matter which way you look at the idea of putting quad onto the silver disc, there's always drawbacks, which explains why we are in the mess today with SACD, Video-DTS and now Bluray.
I think what happened is that Brad Miller died. He was the force behind those DTS surround CD releases. Things dried up after his passing.

The discs were clearly marked as requiring the use of a DTS decoder. DTS decoding was built into many DVD players.

That was the second missed opportunity for a popular discrete quad/surround music format!
 
CDs have digital flags, to indicate the presence of absence, of pre emphasis. There are also digital flags, to tell players that can detect them, that a file is MQA or HDCD, which also means, they are not officially compact disc.
MQA and HDCD flags are magic sequences buried within the audio data itself. As such they are officially compact discs. It's just that when played as pure red book audio CDs they have some extra added low level noise which is the encoding of the MQA or HDCD data in the low bits of the audio data.
 
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