MQA-CDs over SPDIF - No MQA?

Firstly I will clarify I am playing with this out of curiosity, MQA CD is a 16bit/44.1KHz format that has less information than the original 16bit/44KHz redbook format (some data needs to be used for MQA authentication, etc).

However, I have an MQA CD and when I play it on my CD transport (Cambridge CXC) connected to my Rossini, I see no MQA flag on the Rossini. I tried a different player (Oppo BDP-93) and it doesn’t show MQA either.

Interestingly, if I rip the CD to an AIFF file (via XLD) and add it to Roon, it shows as MQA and plays as MQA on Rossini.

So the question is: Does the dCS rendering engine not recognize an MQA stream that is 16bit instead of 24bit?

Some might argue that the transport or BluRay players are not bit perfect, but I don’t think this is the case. Would be nice to know whether it has worked for someone with, say, a dCS transport.

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This explains what is happening:

You have a regular CD Player (not MQA-enabled). It will output (optical or coaxial) a not-yet MQA unfolded signal. The input of your Rossini DAC is what is shown on the display (not MQA yet). However, after being fed by the signal of a MQA CD, your Rossini will do the 3 unfolds.

If you rip and play through Roon, then Roon will do the (first) unfold, and present a MQA tag to your Rossini.

And then there is this:

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As I posted in that other thread, (aside from Roon), the dCS platforms have no issue recognising 16/44.1 MQA-CD FLAC rips as long as the tracks are properly MQATagRetored. They then have no issue being MQA rendered via UPnP streams on dCS platforms.

The MQATagRestorer application ensures the FLAC file header get the proper MQAEncoder and Original SampleRate tags.

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If ripped with XLD, Roon recognizes it is an MQA file (even with AIFF encoding) and plays accordingly.

The point about not doing unfolding (ie only rendering) when the signal is SPDIF is well taken. I assumed that the MQA CD did not require any unfolding (there is no bit depth to unfold when you only have 16bit). I expected the rendering info would be just there, available, but I guess this is not the case - some cursory “unfolding” is required.

Now I will summarize what I think about this MQA SCAM: 16bit/44KHz with some of the already limited redbook bandwidth used to line up Mr Bob Stuart’s pocket is complete BS. No wonder they share the initials. I wish BS complete failure.

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I’m not sure if I would call it a scam necessarily :wink: , but I’m pretty sure MQA’s inception was immediately after the failure of DVD-Audio (and Meridian’s MLP licensing failure along with it); MQA was clearly an evolution of MLP.

As a technology, MQA is is well suited for the early 2000 (3G Wireless era). Not the 2020s. Bob moved too slow :rofl:

MQA as a method to compress higher res into a smaller package is not unreasonable. I get that.

MQA as a method to fix ADC issues is nonesense. If there are any ADC issues you can fix them in standard PCM.

MQA packaged into a 16bit/44.1KHz format is such a blatant moneygrab with NEGATIVE VALUE - you’re literally dropping musical information to give BS some money - It makes me puke.

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I have a non MQA meridian F80 ( all in one cd / amp / speaker unit circa 2007 ) . If I treat it as a cd transport and connect it via optical out to my meridian 808 MQA dac I am able to get full mqa decoding up to 24/352khz. The explanation I have been given is that the f80 sends the signal bit perfect and lossless . I will try the same experiment into my bartok once I can source a suitable optical cable .
Re MQA in general , I find new recordings to be exceptional eg Meiko / Chantalle Chamberland / Bob James) but whether that’s down to a decent production or MQA specifically I cannot say .
This being said , when I stream an MQA track over wifi via Tidal ( on my Astell kern sp1000 / Audeze lcdi4 combo ) I hear no difference compared to the DSD equivalent track which I have on my SP1000 harddrive . Same when I rip and store MQA CDs and I think that is pretty impressive as the MQA file size is so much smaller .

The explanation is correct. In principle ANY CD player or transport that is bit perfect will do the same.

This will not work as per my original question. MQA out of the bitstream is identified in the dCS players via the network card which does the unfolding - or in the CD case just the authentication since there is no data to unfold as it is 16 bit.

On the other hand, if you rip the CD into a redbook file and stream it to the dCS with say Roon, it WILL be recognized as MQA - it is because it is going through the network card.

As a side note, if you unfold the MQA signal elsewhere and feed it to any of the inputs, it will switch the M1 filter on. There’s a process in this unfolding where that signaling of a unfolded PCM stream is used triggering the M1 filter in the dCS units.

I find MQA processing to be somewhat of a “sound beautifier” or “seasoning”, much like tone controls but more sophisticated. Actually akin to a very very mild autotune.

There’s also the “white glove” versions (most of which sound amazing) but in this case I will venture the sound improvement has everything to do with careful remastering and very little to do with MQA itself.

As for MQA CDs, the issue I have is the signal we get is not even 16bit/44.1KHz! Some bit depth needs to be used to authenticate MQA so you end up with worse absolute resolution than redbook CD. Maybe the “MQA seasoning” compensates for the lower resolution, that I cannot tell.