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MQA arrives on Tidal

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There is some Ornette on there . About as edgy as it gets for now.
Station to station has also arrived .

I ordered a explorer 2 in a slightly drunk Mqa leap of faith. Can anyone tell me whether that does all of the local unfolding or just the last piece after the tidal desktop . The MA site isn't very forthcoming
 
On a slightly cynical note, will MQA be a vehicle to recycle and sell more back catalogue music or will this extend to new releases?
 
Jim Audiomisc said:
However do you not mean by the above that the *encoded* version is 24/44.1? Not that the source material was 24/44.1 which someone then 'MQA encoded'.

If so, that may explain what wasn't clear to me in your earlier comments. You seemed to me to be saying that a 24/48 LPCM *source* was being MQA encoded. Which makes no sense. Although I'd agree that the track record of the music biz shows that they often do pretty daft things.
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The source material is 24/44.1. The MQA unfolded file is 24/44.1

Other 24/48 source material masters have been MQA encoded. And in that case the MQA unfolded files are 24/48.

Why do you say this is pretty daft?
 
drummerman said:
On a slightly cynical note, will MQA be a vehicle to recycle and sell more back catalogue music or will this extend to new releases?
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MQA is IMO mainly a vehicle to improve streaming services' SQ.

Naturally there are new releases available in MQA.

I'll give a couple of examples I know well:

I've already mentioned Andras Schiff - Encores after Beethoven; Phronesis - Parallax is also a recent release.

Both are very good IMO.
 
johnhunt said:
There is some Ornette on there . About as edgy as it gets for now.
Station to station has also arrived .

I ordered a explorer 2 in a slightly drunk Mqa leap of faith. Can anyone tell me whether that does all of the local unfolding or just the last piece after the tidal desktop . The MA site isn't very forthcoming
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It must do all of it. After all, it's not a a Tidal/MQA DAC. It's an MQA DAC that, presumably, will work with all MQA files, whether presented by Tidal or otherwise.
 
radamel said:
MQA is IMO mainly a vehicle to improve streaming services' SQ.

Naturally there are new releases available in MQA.

I'll give a couple of examples I know well:

I've already mentioned Andras Schiff - Encores after Beethoven; Phronesis - Parallax is also a recent release.

Both are very good IMO.
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Good start. Thanks
 
davidsrsb said:
It's very likely anything 44.1 is not a master.
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Perhaps. The MQA logo is green whilst playing it and not blue.


(...)the MQA display indicates that the product is decoding and playing an MQA stream or file and denotes provenance that the sound is identical to that of the source material (indicated by a green light in the App). ‘MQA Studio’ (indicated by a blue light in the App) is playing a file which has either been approved in the studio by the artist/producer or has been verified by the copyright owner.
 
radamel said:
The source material is 24/44.1. The MQA unfolded file is 24/44.1

Other 24/48 source material masters have been MQA encoded. And in that case the MQA unfolded files are 24/48.

Why do you say this is pretty daft?
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Two reasons in combination.

1) The point of the 'origami' or 'unfolding' is to try and reproduce the HF which is at frequencies too high to be carried by plain LPCM at 44.1k. So if the output sample rate after MAQ 'decoding' is still 44.1k, it can't be unfolding any such HF or giving any 'sharpening'.

2) The 'bitstacking' would be using some of the least significant bits to *also* provide 'HF hints' - again if there isn't a change in the sample rate, that can't happen.

So on the basis of the MQA documentation, it's daft.

Of course, there may be some kind of 'secret squirrel' changes being applied which they've not told anyone about. But if so, they can't be extending the spectral sharpness by adding in anything above 22.05kHz.

Do you have any way to do a sample-by-sample comparison of the sample values? Subtraction might give a clue as to what might be happening. Unless, of course, it simply someone having glued an 'MQA' label on plain LPCM because they think this will make it sell better. Or maybe a error. i.e. daft.
 
The MQA decoding of the LSB payload could still be recovering some of the lost LSBs, maybe giving 16/44.1 rather than 14/44.1. In this case MQA may be being used as an inefficient container of standard CDDA
 
Jim Audiomisc said:
Two reasons in combination.

1) The point of the 'origami' or 'unfolding' is to try and reproduce the HF which is at frequencies too high to be carried by plain LPCM at 44.1k. So if the output sample rate after MAQ 'decoding' is still 44.1k, it can't be unfolding any such HF or giving any 'sharpening'.

2) The 'bitstacking' would be using some of the least significant bits to *also* provide 'HF hints' - again if there isn't a change in the sample rate, that can't happen.

So on the basis of the MQA documentation, it's daft.

Of course, there may be some kind of 'secret squirrel' changes being applied which they've not told anyone about. But if so, they can't be extending the spectral sharpness by adding in anything above 22.05kHz.

Do you have any way to do a sample-by-sample comparison of the sample values? Subtraction might give a clue as to what might be happening. Unless, of course, it simply someone having glued an 'MQA' label on plain LPCM because they think this will make it sell better. Or maybe a error. i.e. daft.
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Sorry, I don't. Actually I just have the MQA version.

It's not plain LPCM as the DAC identifies it as an MQA file (green light).
 
Archimago's latest take

Conclusions:
1. As shown by the Madonna and Bruno Mars tracks, there are obvious non-hi-res albums out there in the "Masters" collection (no surprise).

2. MQA achieves its purpose with "smart" compromises.

3. If you're streaming TIDAL HiFi/Masters today without an MQA DAC, leave the software decoding of MQA turned ON. No point listening to a non-decoded MQA file with clearly inferior noise floor.

4. Ultimately, subjectively, it's about how MQA "sounds". This is true of course with any lossy compression scheme - for example, it's not really just about the intellectual knowledge that MP3 is lossy that is the problem, it's whether the quality of the encoding/decoding compromised transparency for the listener.
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Bottom line: TIDAL/MQA streaming does sound like the equivalent 24/96 downloads based on what I have heard and the test results (not that I think much of the mainstream music out there is true high-resolution of course). I'd certainly be cautious about claims that the 24/44 or 24/48 files sound "better" when non-decoded compared to standard 16/44 CD or that the "deblurring" makes a significant difference. The real question is still whether the album itself sounds good and truly high-resolution to start off with.
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The clear assertion from Bob Stuart et al in MQA Ltd. is that MQA enables low bit-rate streaming of higher bit rate music files by effectively losslessly "hiding" the higher frequencies under the noise floor of the baseband 24/16 file. In parallel with this the MQA decoder attempts to remove the pre- ringing artefacts which have heretofore been an inevitable part of the "digital" sound caused by steep digital filters which have pre ringing in the time domain. The higher the sample rate of the original recording the better sounding the de-time-blurred rendered file will sound.

Nonetheless I find even low bit rate "masters" - like Madonna's Material World (mastered in 16/44) - have improved sound imaging and a more involving musical sound when decoded by the Tidal MQA app. And the sound improves further as one listens to higher bit rate masters (all things being equal - many albums are badly compressed.....).

As the sampling rate improves timing errors decrease anyway - the reconstruction filters can be much less steep. Even Bob concedes that decoded 24/384 masters hardly have any timing improvements compared to the original master. But the 24/384 files are huge and I for one am happy to be able to stream a file that decodes to that a high bit rate master, rather than have to pay €20 per high res download.

In the 70s I was happy to pay Dolby licensing fees to greatly reduce Cassette Tape hiss. I have no philosophical issue with rewarding MQA for this innovation in sound , which offers me real musical benefits.

To those who fear the future loss of purchasable downloadable high res files I would like to point out that the current hi-res downloadable catalogue is a very small and expensive subset of the music most people listen to. I would indeed expect that if MQA becomes widely used then vendors of hires files may well have financial problems.

Given the desirability of single inventories I can not see vendors being able to charge a large premium for MQA files in future, so those who care to buy a decoder, get the original hi-res file for little or no extra cost. This is a positive musical development in my opinion.
 
Markpd said:
The clear assertion from Bob Stuart et al in MQA Ltd. is that MQA enables low bit-rate streaming of higher bit rate music files by effectively losslessly "hiding" the higher frequencies under the noise floor of the baseband 24/16 file.

Nonetheless I find even low bit rate "masters" - like Madonna's Material World (mastered in 16/44) - have improved sound imaging and a more involving musical sound when decoded by the Tidal MQA app.

As the sampling rate improves timing errors decrease anyway - the reconstruction filters can be much less steep.


Given the desirability of single inventories I can not see vendors being able to charge a large premium for MQA files in future, so those who care to buy a decoder, get the original hi-res file for little or no extra cost. This is a positive musical development in my opinion.
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I'm not sure he has claimed this is 'lossless'. The folding process as specified in the patents, etc, looks to me like not being so. So it might be wise for people to avoid making that claim. And since the folding tends to *add* components that weren't in the source (and which unfolding may not remove) 'lossless' here isn't the same as ensuring the waveforms are preserved though an encode-decode path.

As with some earlier comments, the feeling that even 'low rez' masters are 'improved' is an odd one, and implies MQA is an 'effect'.

And although people seem to have trouble with the idea, you don't need high sample rates for accurate time alignment.

Nor does the output have to 'ring' if you choose appropriate recording and reconstruction filters to avoid it.
 
As an OT aside it occurs to me to add something which some may find interesting...

I think it is a a pity that more people don't have a good understanding of the basics of Digital Audio. With that in mind it occurs to me to point to some documents I scanned and made public a few days ago.

You can find them at

http://www.torrens.org.uk/ukhhsoc/makers/QUAD/General/Watkinson_Presentation_on_CD/index.html

John Watkinson kindly gave the UKHHSoc permission to make them public. They are a copy of his presentation notes for some lectures he gave to QUAD dealers, etc, back in the 1980s to bring them 'up to speed' on Audio CD. They are xeroxes of notes, and *NOT* about MQA. But I'm mentioning them in case anyone finds them useful or interesting as an outline of the basics. However if you have a copy of John's "Art of Digital Audio" you'll have already seen better copies. :)
 
Jim Audiomisc said:
John Watkinson kindly gave the UKHHSoc permission to make them public. They are a copy of his presentation notes for some lectures he gave to QUAD dealers, etc, back in the 1980s to bring them 'up to speed' on Audio CD.
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Interesting historical perspective. Thanks!
 
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