Testing MQA: Is it worse than FLAC?

[GoldenOne]

TLDR: MQA isn't lossless, is arguably worse than normal flac, and is seemingly nothing more than a (quite effective) scheme to generate licensing fees. With the frustrating addition that if you are a Tidal user, even if you have no MQA dac, and use the "Hifi" streaming quality setting, MQA encoded/lossy files will still be served to you. And the only way to avoid that being to switch to Qobuz.
If you disagree with this post, or if someone from MQA/Meridian is reading this, it would be excellent if you could provide alternative evidence supporting MQA's claims. If they are true it'd be EXTREMELY simple to demonstrate/prove and so the current lack of any evidence other than marketing claims is concerning.

I figured that given how aggressively Tidal has been expanding their use/incorporation of MQA (with now many redbook files coming MQA encoded even if they are not able to be unfolded to hires), and there seems to be an awful lot of debate about whether or not MQA is good or lives up to the claims, and not much testing going on, (including lack of evidence from MQA themselves), I should try to remedy that.

I'd like to preface this by saying a few things:
- This is not a dig at any manufacturer that incorporates MQA. MQA has been very successful from a business/marketing standpoint, and so customers are demanding it. Therefore its understandable that manufacturers like PS Audio are going to add it to their products even though they openly say they do not like MQA. 
- If you feel MQA sounds better, that's totally fine. Lots of things sound good and objectively perform bad, many tube amps for example. This is not addressing what sounds good to YOUR ears, this is addressing the hostile business practices and unsubstantiated marketing claims of MQA. 
- Further testing will be done by performing some null tests with the final unfolded analog output of an MQA dac soon, and i'll post here once that is completed.

- I am not writing this because I have an issue with MQA existing, I am writing it because MQA's business practices are detrimental to anyone who is not using their product (as we can no longer access native hires content), and arguably to those using their product too (because evidence shows MQA is likely inferior to native FLAC at any sample rate). MQA is POTENTIALLY a solution to a very niche problem (the need for HiRes audio when data is limited), but is being forced upon everyone in the market.

This post is intended to answer test and answer a few questions about MQA, namely:

1) Are MQA releases the same master as non-MQA?

2) If you don't have an MQA dac, is standard FLAC and MQA-FLAC the same / does MQA provide a benefit even on a normal dac?

3) Is unfolded MQA lossless or as good as native HiRes?

 

This is normally quite tricky to test because MQA ensures that there are no native HiRes releases for tracks that are released in MQA on tidal. So you cannot directly compare them. This is actually my biggest issue with MQA. If it were simply a choice of whether one wanted to use MQA or native HiRes, this discussion wouldn't be needed. But MQA seems to prevent the native HiRes release of tracks elsewhere, and in some cases some HiRes tracks have even vanished from other platforms such as Qobuz once the MQA Tidal version comes out.
However, there are a couple which seem to have slipped by.

Absofacto's "Thousand Peaces" for example has ONE of the songs in 96khz on qobuz (the rest are 44.1) and 88.2khz via MQA on tidal. (The fact that the MQA version isn't even the correct base sample rate is concerning in itself) I initially tested this, however it turned out that the Qobuz redbook and tidal redbook versions were different, meaning they are using different masters and could not be directly compared.
 

Answer 1: MQA/Masters SOMETIMES uses a different master source. Meaning the file formats themselves cannot be compared as the information/recording itself is different. This is likely done to give the impression of sounding better even though it's nothing to do with the file format.
 

So then, we need a different test track/album. Sam Smith's "The thrill of it all" however was ideal. It has a native 24 bit 88.2khz version on qobuz as well as the standard 44.1khz release. And on tidal there is also a 44.1khz release and can be 'unfolded' to 88.2khz via MQA. Meaning we can compare identical sample rates.

The first thing to do was to check whether the Tidal and Qobuz redbook/non-MQA files were actually the same. ie: Are tidal and qobuz using the same master for the song. To do this I downloaded the Redbook 16 bit 44.1khz version from Qobuz, and then the same from the release on tidal that was not marked "Master".

Deltawave showed that these two files were 100% absolutely bit for bit identical. So we can conclude that Tidal and Qobuz are using the same master for the song. Perfect.

 

Next, I downloaded the "Master"/MQA release, but without any MQA unfolding. ie: keeping it as a non-MQA dac owner would be playing it. Both these files are 44.1khz, but are not the same. In fact they are only 0.43% bitperfect with a 40dB null (24 bit accuracy is 146dB) We can see that the master is clearly the same as the majority of the track is identical, but the MQA version has a significant amount of high frequency noise compared to the lossless FLAC.


 

(Y axis is frequency, X axis is time. Green means that part is the same, purple/red means it is higher or lower in level and different from the original).
Just as a reminder, this is a direct digital rip, not an analog recording, so these differences are NOT due to variation in my recording or the DAC(s).
 

Answer 2: If you do not have an MQA DAC, MQA should be avoided, the content is NOT the same as the lossless original, and has more high frequency noise.

Additionally, MQA releases in many instances seem to be several dB louder than the redbook version. Again likely done to give the illusion of sounding better.

So then, now we need to see what happens if you unfold the MQA version to 88.2khz and compare it with the native 88.2khz version. I did this by using Roon, which has MQA decoding support, and recording bitperfect output, then comparing against the native hires 88.2khz version from qobuz.

Now things are really quite messy. The unfolded version differs significantly from the native hires, with again a lot more high frequency noise, as well as a band from about 11.5khz to 13.5khz where content differs a concerning amount in this specific instance.


 

Therefore

Answer 3: No, MQA is NOT lossless (a claim which MQA has recently removed from their marketing material), and even when unfolded does not match native HiRes content. I would love to test a full decoder/renderer, but MQA does not allow any "Full Unfolding" device to have a digital output, meaning we can never test a fully unfolded file other than by recording analog output of a DAC (which will never be perfect), and thus we will never be able to check if it is indeed identical to the original.
 

Additional arguments:
 

• MQA is actually probably worse than native playback. MQA makes it basically impossible to obtain a "normal" and MQA version of the same hires file. BUT, Stereophile did manage to convince them to send an MQA encoded single-impulse file. Their testing showed three things:
  1 - Playing back an MQA encoded file on a non-MQA dac caused issues, and created an asymmetric impulse response.
  2 - Playing it back on an MQA capable dac, it was minimum phase, not linear.
  3 - Playing back a NORMAL, non-MQA encoded impulse response file, with the MQA filter turned on on the DAC, produced an IDENTICAL result to the MQA file, suggesting that MQA is nothing more than a basic minimum-phase upsampling filter in this situation, and absolutely nothing to do with the source file. https://www.stereophile.com/content/mqa-tested-part-1
  There is significant evidence from multiple third party sources to show that MQA has all sorts of problems. http://archimago.blogspot.com/2018/02/musingsmeasurements-on-blurring-and-why.html
  

 

• MQA incurs an additional cost to you. You are paying for the licensing fees that are tacked on to products to get MQA support, and at every other step in the process. A good post from the manufacturer Linn is available here: https://web.archive.org/web/20201111211105/https://www.linn.co.uk/blog/mqa-is-bad-for-music Given as we have now demonstrated that MQA is NOT a substitute for native HiRes content, its hard to argue that MQA is doing much more than charging you for a sub-par version of something you already had (native hires music). If you want the best quality, demand native hires releases, not licensed, closed-source, proprietary compression. Schiit audio has also spoken on it: https://www.schiit.com/news/news/why-we-wont-be-supporting-mqa

 

• MQA IS NOT sourced from a HiRes master. Even if you are happy with it not being lossless, it is not actually even compressed from a HiRes source. Neil Young removed his music from tidal when after providing 44.1khz masters, Tidal suddenly released MQA versions, which would have been created simply by altering/upsampling the original. He did NOT provide them with HiRes masters to release in MQA, and you can read about this here: https://neilyoungarchives.com/news/1/article?id=Tidal-Misleading-Listeners
  
  "Tidal's master is a degredation of the original to make it fit in a box that collects royalties. That money ultimately is paid by listeners, I am not behind it. I am out of there. Gone. My masters are the original."
  MQA is at least in some situations simply an upsampled version with a licensing fee slapped on.....
   

 

• There is ZERO proof of any of MQA's claims. There is absolutely zero evidence to support any of their marketing, claims that they can fit 24 bit 192khz content into a 16 bit 44.1khz file, and in fact, all objective evidence and testing so far (including this post) conclude that MQA's claims don't make sense at all. The claims they make would be VERY easy to demonstrate and prove if they were true....
  Most MQA content cannot be obtained in native HiRes anywhere. And they do not allow any "full unfolding" device to have a digital output to prevent anyone from recording or testing the result.

Plenty of manufacturers have spoken out about MQA as well, some more aggressively than others.
- Linn: https://web.archive.org/web/20201111211105/https://www.linn.co.uk/blog/mqa-is-bad-for-music
- Schiit: https://www.schiit.com/news/news/why-we-wont-be-supporting-mqa
- PS Audio: https://www.youtube.com/watch?v=lPfmWKjiccA

Thanks for reading, hopefully this helped some people!

 

[GoldenOne]

1 hour ago, saturdayboy said:

I think your ignoring the question that might be most important to some:

 

Does an MQA file played through a dac with full MQA capabilities sound better than the 16/44.1, 24/96, 24/192, etc.. alternatives?

 

Who cares if it isn’t truly lossless if it actually sounds a little better?

 

I’m starting to see posts that claim MQA cd’s sound better than SACD’s. It certainly is interesting.

 

Unfortunately its a question that can't be properly addressed.
Though I did address in the post WHY it can't be addressed.

MQA does not allow any device with 'full unfolding' capabilities to output a digital stream. It is ONLY allowed for analog only output devices. 
This means that we can never get a proper test of the native file vs fully unfolded MQA.
This is also assuming that you can find an MQA track that has a 192khz native hires release.

We can ONLY test by recording and comparing the results of analog output.
I will be doing some null tests recording from the analog output of a fully MQA capable DAC using the ADI-2 Pro ADC (performance info for which can be seen here: http://archimago.blogspot.com/2020/09/measurements-rme-adi-2-pro-fs-r-black.html ) 
This will not be able to tell us if the fully unfolded file is 'bit perfect' as it is recording from the analog output. But it will be able to show if there are any obvious discrepancies between native and MQA.

I'll additionally compare the audible band only content of the fully unfolded MQA file to the native FLAC audible band content to see if there are differences.

Its not the most ideal test, but unfortunately MQA has deliberately made it impossible to do an ideal test.

In regards to MQA being better than SACD, its an apples to oranges comparison.
SACD is 1 bit and so the quality of playback will be much more dependent on the source file, how it was produced and modulated down to 1 bit etc. (Much in the same way as you can use HQPlayer DSD modulators to get some pretty fantastic sound out of otherwise mediocre DACs by effectively 'replacing' the delta sigma modulator)

Whereas MQA is still PCM, and so will be more dependent on which DAC you're using.

Subjectively, to me, MQA sounds similar to minimum phase upsampling. And other third party testing suggests that it's quite likely a lot of MQA content IS just minimum phase upsampling. 
What's the best subjectively will always be up for debate unfortunately. So I won't get into that other than being open about the fact that I don't like it though mostly because of the attached business practices, if it were a choice it would actually be nice to have for certain situations where data or storage is limited. But for anyone at home with a good internet connection or cheap hard drive to put their music on, MQA is a solution to a problem that doesn't exist, being forced upon you and something good (native hires audio) getting taken away in the process.

[GoldenOne]

On 4/2/2021 at 10:27 PM, manisandher said:

I've posted files from the same master in the past:

 

 

The downloads are still available for anyone who wants to take a listen...

 

Mani.

I ran some comparisons on these in the same way as the original post.

A and B are nearly identical. Differences maybe due to dithering?
Then in file C suddenly we get a lot of variation and high frequency noise again as seen in the original post. C is definitely MQA


A vs B:

 

A vs C:




B vs C:

[GoldenOne]

1 minute ago, saturdayboy said:

Pretty respected, including here. Why would they do that, and why aren’t you calling them out for perpetuating the lie like you are MQA inc.?

Because they're a business. 

Because if customers are demanding something, then a manufacturer will do what drives more sales. 

 

See ps audio for example. They support mqa but also have a video where Paul explains he does not like mqa. 

 

Just because a manufacturer makes their products compatible with something it is not a statement of agreement with mqa's marketing claims.