KSTR
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We could simple try to upload a file like OP did, preferably some avantgarde/electronic music (but within the allowed limits for "normal music") with the clearly defined test signals buried/hidden.
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MQA Deep Dive - I published music on tidal to test MQA
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Yes, Tidal does the software decode of MQA files it delivers. It just won't do the "final unfold" which people say is just a resample. If so, you don't need that and you get free decode of what is there. And you can use any DAC you like. I for example use RME ADI-2 DAC which doesn't support MQA. But my Roon player does and it too decodes it for free for me.
I am sure by now they have put in an input trap for test tones.
And one would have to be willing to break terms of service agreement.
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Someone could indeed do that. Personally I would bet that this would not enable whomever did so to escape the ad hominem attacks that have been needlessly (and intentionally) mixed in with the substantive objections to what @GoldenOne did, but I would love to be proven wrong!
I read through it. It is a lot of careful work to analyze what has happened to the MQA version of the same baseline, i.e. undecoded MQA versus the CD version. He rightly points out that we don't have the full information to know what exactly went on these conversions. But trusting what is there, he has discovered that the MQA version has a slight low-pass filter applied in addition to embedding its bits in the high frequencies. It is possible that a de-emphasis/re-emphasis is part of the MQA scheme as to allow better ability to encode its bits in high frequencies. He also says that likely the impact of the MQA additions is not audible:
"Overall, the good news for those using non-MQA playback systems is, though, that the 2L examples generally show so little HF that it seems doubtful that the presence/absence of HF would be particularly audible if the Red Book filtering itself is inaudible because the signal levels are so low. The main possible exception above to this generalisation may be 2L file 145 which has more HF, but this is still at a generally low level that may well not be audible if someone doesn’t notice the ‘Red Book’ filtering. Note, though, that the above examples were chosen for analysis at random, so may not fairly represent the behaviour of some other available recordings. "
It is very good work and is what we need instead of shouting, etc.
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@Hayabusa said "that does MQA test in the correct way." That means they're asking for someone to re-do the test in a way that does not break MQA's terms of service.
And once again, the point here is that MQA has acted as if there is no "real music" that does not contain signals that the MQA encoder considers "illegal." That has not yet been established.
A quote:
Part of this dilemma arises because – if I understand correctly – MQA are concerned that if people know both the input precise input to MQA encoding and its resulting encoded output they can then this information this to work out the details of MQA encoding and decoding which are currently kept as ‘trade secrets’ by MQA. Hence anyone making and distributing MQA encoded material is required prevent people having access to precisely what was fed into the encoder. The implication being that any non-MQA hi-res alternative on offer must differ significantly from what was given to the encoder.
This is really devastating for MQA if true. How can anybody argue that MQA is somehow good for the consumer of music when this is true.
The outfit he used doesn't do custom encodings of MQA. For best effort, we need to go to a mastering house that does. Do we have any members in the Pro community that could facilitate providing the content and getting it converted by such a mastering house? We could cough up some money for the service if people value it enough. I will donate up to $250 toward it.
I see the first point. I thought he was asking someone to repeat GO's effort but with test tones in the data space that MQA will encode.
On the second point, I think you misunderstood. MQA will encode test signals IN THE DATA SPACE they allocated for encoding - the lower Shannon Triangle.
Amir explained it many times.
danadam
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It is free for you but apparently roon is billed for each decoding: https://community.roonlabs.com/t/why-do-manufacturers-support-mqa/155965/135?u=kenneth_jonge
I wonder who is paying for that.
There is no evidence of this being true. Nor do I see it being practically workable at all. What is MQA going to do? Go sue warner for sending out the same high res master to Apple and Amazon???
Why?
Jim theorizes that a low pass filter is used as part of the process, which also common in standard mastering.
And I don't think an exact comparison will give the encoder away, since it's dynamically optimized for each piece of music or even within each piece of music.
One would need to do this a thousand times...much cheaper to just pay to use the encoder. Also avoids a lawsuit.
I almost wrote I hope someone doesn't repeat that argument and here you are.
Once more, I said the playback is free to me, the consumer, the very people consuming MQA content.When you buy a DVD player with analog out, it comes with stereo decoder for Dolby in there. They paid for a license fee for that. Are you going to hold that against Dolby? There is a cost of doing business here. Roon has a ton of subscribes like me that bought it because of tight integration with Tidal. As part of the money they received from me, they are paying licensing fees to MQA. They are not doing that without a source of revenue. Native MQA playback is an asset for Roon. Just like it is for DVD player decode of Dolby AC-3.
I wonder if you can store MQA in an ALAC container, otherwise Apple might just be Anti-MQA in principle. Even if record labels like 2L want to be douche bags and booby trap their records with MQA they can't.
I wonder why you care. They also pay huge amounts of money to metadata providers that Roon shows. You are upset about that too? Or understand that they charge a lot more for their player than JRiver does because of such features?
I think this is very unfair to a small, specialist audiophile label.
It would be trivial to use ALAC instead of Flac for MQA bitstream. MQA would happily modify their software to do so should that be what Apple needs to adopt it.
You can. Just convert the MQA FLAC file to ALAC, there are free tools to do that. MQA is independent of FLAC, - I found MQA in some WAV files.
I don't think Apple publishes Hi res at the moment only acc so I don't really onderstand what you are saying here. Don't companies have to sign a contract to licence MQA? Is that public? Somehow MQA does not really seem all that trustworthy to me as a simple consumer.
MQA publishes a list of streaming services it uses - a very small list. What are you throwing shade at here?
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