An Archimago contributer and his listening tests of MQA

Apart from any criticisms about MQA, this is how a review of equipment, recordings or recording formats should be conducted and written up.

Yeah, I’m talking to you and your cohorts, @John_Darko.

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It takes people like Archimago to come forward to reveal the truth. Ironically ‘fake news’ and ‘fake claims’ are common these days and we need to be vigilant and not fall into beliefs. As I posted on another thread, 16 bit MQA CD is nothing more than a regular CD treated with de-blurring filters; they hardly classified as high resolution. Here is a quote from him…

For those of you technically inclined, the result from Agitater and friends is of no surprise! Remember that MQA-CD is simply 16/44.1 PCM that might be mastered differently to change the sound which is why it’s so important examining which mastering was used as Agitater did. However, since the data must include the MQA control stream somewhere (MQA identification, crypto signature, instructions for dithering/noise shaping/filter selection), this means that one of those 16 bits will be used to contain MQA data instead of your usual music data, making the resolution at best 15-bits. And since there are no lower 8 bits like in “hi-res” MQA at 24/44.1 or 24/48 to unfold the ultrasonic octave, the only pseudo content above 22.01kHz is the result of the leaky filters used by MQA (not even a lossy reconstruction). There is absolutely no justification for calling these MQA-CDs “high resolution” at all! If anything, technically, they rob resolution from standard CD!

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Regarding: "There is absolutely no justification for calling these MQA-CDs “high resolution” at all! If anything, technically, they rob resolution from standard CD!"

This was very easy for me to see with my own eyes a while ago, when I was comparing the Tidal 1st unfold in Roon vs Hi-Res purchase vs CD quality, for the album MAGNIFICAT and a couple other albums where you are able to purchase the same mastering (DXD version) that these other versions came from.

The CD quality version I purchased turned out to be MQA CD (unexpected when I bought it). And when I did a digital capture and looked at the spectrum analysis, it looked yuck - worse than ‘normal’ CD quality.

When I sent my results privately to a few very clever people that I greatly respect (whose products support MQA) - they agreed, MQA CD is crap.

The MQA 1st unfold (up to 96kHz) is very much like the Hi-Res that you can purchase though (when the mastering is the same), as Archimago himself agrees:

From Archimago:

"Objectively with the songs I examined, the software decoder works well to reconstruct what looks like the equivalent 24/96 download."

and

"Bottom line: TIDAL/MQA streaming does sound like the equivalent 24/96 downloads based on what I have heard and the test results"

https://archimago.blogspot.hk/2017/01/comparison-tidal-mqa-music-high.html

This applies to the 1st unfold only (up to 96kHz)… he’s done plenty of analysis on the stuff after the 1st unfold, which doesn’t need repeating of course.

You could ask, if I have a 24/96 master and need to deliver it in 16/44 form, is it better to keep 16 bits and cut off at 44k, or preserve only 12 bits and use the lower bits to fold in the higher frequencies? A question about which engineering trade off is best. You could make meaningful experiments.

After all, engineering is the art of optimizing under constraints.

But this case, MQA CDs, reminds me of a zen koan: two students are sitting on tatami mats, meditating, when suddenly the master runs in, brandishing a katana, and screams “If you say a word I will cut your head off! If you don’t say a word, I will cut your head off!” What is the answer? The more enlightened student jumped up and wrenched the sword out of the master’s hand. Wisdom lay in questioning the premise.

The answer to the MQA CD koan is, why would you do that?

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[quote=“AndersVinberg, post:4, topic:47182”]
You could ask, if I have a 24/96 master and need to deliver it in 16/44 form, is it better to keep 16 bits and cut off at 44k, or preserve only 12 bits and use the lower bits to fold in the higher frequencies?

In my opinion using just 12 bit (13 bit dithered) and the remaining 4 bit to recover ultra-sonic component is a possibility since they have already done with 24 bit MQA. I think I came across that Bob Stuart said that the minimum quality is 13 or 16 bit sample above 50kHz??

I had to say that when I heard that MQA version of Getz/Gilberto myself when we first got MQA unfolding in Roon I also did not like it all, normal stream sounded way better.

Something like that.
But my point was, why would you bother with MQA squeezed into a 16 bit file?
That’s the premise to question.
Wrench the sword away!