MQA Deep Dive - I published music on tidal to test MQA

[Jimbob54]

If PCM and MQA are equal in audible sound quality, which has the worst processor load for penalty for decoding? With and without MQA hardware? I always listened to Tidal with the Windows App, does that give the full "unfolding"? Or do you have to invest in MQA hardware to get the best out of MQA?

I know these are elementary questions, but I'm more confused as this goes on...

Tidal app, Roon etc can all do the core decode (the first one) to 24/96 or 24/88. The render to 192 etc needs to be done on hardware (the dac basically) or, you can set the software to leave the file alone and pass to a "full" mqa dac which will do the core then render.

From what I have gleaned here, that rendering stage is little more than upsampling.

I think I have that the right way round but it's a bit of a minefield

EDIT- its worth pointing out what when I last used Tidal MQA (a year or so ago) - the majority of MQA files topped out at 24/96 so would be "fully decoded" within the core Tidal app/ Roon and wouldnt need an MQA stickered DAC at all. This is a factor that seems to be overlooked when talking about a hardware "tax" . One is pointed towards such devices when in reality, the amount of content that can be rendered to 24/192 isnt (wasnt?) huge.

 

[Hayabusa]

You seem to have serious problem following a discussion. I explained that I like the technology underlying MQA. You asked if some other technologies are just as cool and I explained that. This has nothing to do with what you as a user and lay person like. Don't ask me stuff if you can't even follow the thread of what is being discussed. And make sure your next post is informative and not complaining in nature or you will get a reply ban.

CFO, we should redefine the F.

 

[amirm]

CFO, we should redefine the F.

For sure. The few of you do take all the fun out of having discussions like this. Seems you can't leave your emotions at the door and focus on contributing technically. Have to just post to complain.

 

[Hayabusa]

For sure. The few of you do take all the fun out of having discussions like this. Seems you can't leave your emotions at the door and focus on contributing technically. Have to just post to complain.

I agree, but in this case you were putting oil on the fire and could have been nicer and more fun.
Lets all be nice now?

 

[Music1969]

You think you got harmed? No, *I* just got harmed to the tune of nearly $20!!! Read on.

I looked up the album you bought on Tidal. It is available and it is indeed in MQA. I went to capture its spectrum as it played and was very surprised to see the brick wall above 22 kHz! So I got curious as to what the original 96 kHz version looked like. Fortunately one of my favorite high-res stores, Prostudiomasters had it:

View attachment 132505

Notice how they sell both the MQA and non-MQA versions. Cough up the money and buy the album. The non-MQA is indeed, non-MQA:

View attachment 132507

This is what the spectrum of the third track looks like (similar to tracks 1 and 2):

View attachment 132506

Son of gun! The actual (live) recording is at 44.1 kHz but is somehow mixed into a high-res envelop. We know this because some noise has been added there including that one peak at nearly 48 kHz.

The most shocking part is who mastered this: the famous Bob Ludwig!!! From the credits: "Mastered by Robert C. Ludwig "

Un.... believable. This is like buying a $1000 DAC from a famous designer and finding an Apple dongle in there!

You see where the real battleground is? We need to get the masters cleaned up and have them released without loudness compression. That is the battle we should put our energy toward. Not these little squabbles over MQA.

I am going to go on hot dogs and water dinners for the next few days to make up for the $20 loss on this....

For everyone cancelling Tidal and moving to Qobuz, this kind of stuff is there too

 

[Music1969]

Tidal was the same as Qobuz- both offering up to "hi-res" PCM that could be played on all DACs that can go up to 192.

Just to clarify, Tidal never offered anything above PCM44.1kHz before they offered MQA.

 

[Music1969]

I finally caught up on the last few days posts - highly entertaining stuff

I was actually enjoying @GoldenOne 's work but @amirm came out swinging the last couple days, really poking some serious holes in his comments.

And then seeing posts like this about GoldenOne over on other forums like SBAF and APS... that's really not cool.

On other forums I see he seems to be getting 'egged on' by some anti-Amir people.

I cancelled Tidal recently because Apple is going lossless (ALAC) next month.

16/44.1 - perfect sound 4 evar ! The world does not need MQA.

For mobile listening in the car, plane, walking/running, gym, bus/train etc, AAC/Ogg Vorbis/mp3 is absolutely fine.

At home give us ALAC or FLAC without the folding non-sense.

https://www.audiosciencereview.com/...-music-on-tidal-to-test-mqa.22549/post-797385

 

[adamd]

I do not as I have not done any testing of decoded MQA content. Hope to do that soon.

Hi Amir
I appreciate that things have got a little heated round these parts, but I’m sure I’m not alone in looking forward to seeing your results.

I appreciate your interest in MQA as a means of efficient data compression. (Although part of the problem is that it seems to have set out to do something else through the mysterious deblurring process). Clearly (if we assume that this part could be hived off) there is some potential attraction in a scheme to code hi Rez efficiently, but it does inevitably raise conceptual and practical problems about what exactly we are looking to do. After all it’s not easy to establish audibility of anything over 20kHz.

Of course we could in theory set out to identify the musical information and only capture that. But how that could be achieved with time domain sampling is another matter. And that’s assuming that we can easily establish what is musical information and what isn’t.

There may need to be a word to described data compression which is not quite lossless (not mathematically interchangeable) but which consists only of manipulating the noise floor of the file to match that of the original without being exactly identical.

This gets round the wastefulness of flac and other lossless encoders without any need to get involved either in identifying the music or introducing any particular theory of audibility. If there is anything neat about a proposed data compression system then surely it would have to beat this in efficiency as well as equalling it (or at least being very close) in accuracy.

I would therefore (at risk of being annoying) put in a request that you look at least at a
-comparison of 24/96 “master” with MQA

-24/192 master with MQA abs conventionally filtered 24/96 version

- all of the above with 16/96 noise shsped flac version of the master

Anyway I was hoping not to raise the temperature but to contribute to a sober conversation about how to assess the data compression properties of MQA

 

[BDWoody]

25 years from now, when someone mentions MQA, people will have forgotten about it already.

Except former moderators...they will start twitching uncontrollably...

 

[Ultor]

Quick question, am I the only one surprised by the following statement (in Bob's article):

FLAC is a lossless file format, a container for audio data. MQA is an advanced method for coding audio contents. MQA is normally delivered (losslessly) in a FLAC container from the music label. PCM is another type of audio that can be delivered by FLAC. Suggesting FLAC is better than MQA is like saying ‘bottles are better than wine’!

If I'm not mistaken, we must distinguish between Native FLAC (which is the container) and FLAC which is the codec. And it's not for nothing that you can put FLAC in an Ogg container https://xiph.org/flac/faq.html

 

[Jimbob54]

Just to clarify, Tidal never offered anything above PCM44.1kHz before they offered MQA.

Yup. And that, imo is the only reason mqa exists still. Tidal added it as something of a bonus into the lossless tier. Had they already had hires PCM and replaced with mqa it would have been dead in the water.

 

[JohnYang1997]

Yup. And that, imo is the only reason mqa exists still. Tidal added it as something of a bonus into the lossless tier. Had they already had hires PCM and replaced with mqa it would have been dead in the water.

The idea is how do we prove MQA is better than CD quality at the output of a DAC?

 

[Jimbob54]

The idea is how do we prove MQA is better than CD quality at the output of a DAC?

I'll leave that to you guys. The market just kind of accepted the fancy graphs and spiel that it must be better.

 

[Music1969]

The idea is how do we prove MQA is better than CD quality at the output of a DAC?

Go here and compare DXD digital master (PCM353kHz) with MQA decoded and RBCD to the digital master.

http://www.2l.no/hires/index.html?

Compare DAC analogue output and determined if MQA is better than the CD quality (or worse).

 

[solderdude]

The whole issue here is 'perception'.

Technically speaking the MQA container is lossy both in bit depth and waveform accuracy.
Then there is perception. When asked, with certain music, MP3 is even preferred over WAV where it is obvious WAV is the 'better' file.
So perceptionally, caused by a codec based on perception, the MP3 sometimes is preferred.
The same can be true for MQA.

That doesn't make it technically a better codec but could be audible transparent or even preferred but depending on the circumstances also be less preferred.

I am not into this MQA thing, nor have a DAC that decodes it nor have any MQA music so my question would be:
Are there statistically enough well founded reports that show MQA sounds poorer than the same master recording on other formats.

I know, obviously, technically the performance of MQA is poorer... but audibly ?
Using ears only... not knowing something is MQA (properly unfolded) or not. Blind, level matched (one can have different levels).
Has there been properly done research by others ?

 

[Jimbob54]

Except former moderators...they will start twitching uncontrollably...

Look at poor Thomas- he was so wracked last night he could barely type. Nothing to do with the 8 pints of strong ale he necked.

 

[mansr]

All this talk about wasted space is nothing but misdirection. Sure, uncompressed PCM is wasteful with the typical frequency distribution of music content. That's why we have compression algorithms like FLAC that encode only the actual information content, omitting the "blank space." MQA reduces the size a little further by discarding some of the information as well. There's nothing wrong with that per se. However, the way MQA does it is a) ham-fisted (see the mess it made with GoldenOne's test file) and b) reliant on licensed decoders. The same (slight) size reduction could easily be achieved by analysing the files to determine their noise level and dropping anything below it. The danger with such an approach is that once you start discarding information, there is always a risk of dropping something that should have remained. As for the decoder, the only reason I can see for that design is to increase license revenue.

 

[Lunafag]

Something you didn't mention but I value is elegance in efficient coding of music. I have always considered PCM format to be highly wasteful. As a person who has spent decades optimizing technology, it seems like such a poor solution. Going from 44.1 kHz to 88.2 kHz doubles the data rate yet there is hardly any musical information to be gained from that doubling. In that regard, MQA's approach of noticing the statistical aspects of music and encoding that is appealing to me. It is simply neat!

So it's neat at encoding stuff we don't hear? Weird flex but ok. As far as lossy codecs go MQA just wastes my bandwidth. Now, if we had a mainstream sub-Nyquist sampling codec for example, that I would be highly interested in.

 

[KSTR]

I am not into this MQA thing, nor have a DAC that decodes it nor have any MQA music so my question would be:
Are there statistically enough well founded reports that show MQA sounds poorer than the same master recording on other formats.

Unlikely to happen until encoder and full decoder software is available standalone.

 

[PO3c]

The idea is how do we prove MQA is better than CD quality at the output of a DAC?

Wouldn't that crumble any DAC vendors hard work making their 22b or better product precision playing 24b MQA content return a pretty high noise floor around 15b on audio output?