Does MQA work with Roon and my DAC?
Will my Tidal app offer me full MQA quality?
If Tidal sends me a 48 kHz file, does the MQA decoding do upsampling?
Just a number of questions I get asked a lot.
Time for some answers.
MQA uses new insights in how we hear music to reduce the amount of data needed for high
resolution audio.
Weren't we told the same by Dolby: Dolby Digital - which uses lossy compression - should
sound just as good as the original PCM signal.
And it didn't, which is easily proven by the fact that we now have Dolby TrueHD.
MP3 and AAC- also lossy compression schemes - are not identical to the original either.
Whether you hear the difference depends on your equipment, your hearing capabilities
and your listening environment.
In a car at 130 kph you probably won't hear a difference.
And then came MQA, again three characters and again using lossy compression.
So the tech-purists condemned it, even without listening to it.
For when you listen to it over a full MQA enabled system, you will know it often sounds
even better than standard 24 bit 192 kHz PCM.
Watch my video "Is MQA lossless" for more information.
Links at the usual places.
Time for the questions.
You can play MQA files on any device that can also play normal PCM files like WAV, FLAC,
AIF and so on.
What you get then is a quality equal to or better than a normal 44.1 or 48 kHz 16 bit
file.
The quality can be better since usually the original master - or a production master closest
to the original master - is used for the mastering of MQA.
And MQA uses a filtering that repairs time smearing in the production equipment to some
degree.
Furthermore MQA promises to never offer upsampled files; if a master is at 44.1 kHz, the MQA
signal - even when using the full MQA decoding - is also 44.1 kHz.
If the master is at a higher sampling frequency, like 96 or 192 kHz, non-MQA equipment will
see a 48 kHz file.
But when you play it back over software that can do the core decoding - also called the
first unfolding - you will get a signal up to 96 kHz, if the original master was 96 kHz
or higher.
That signal can be sent to any non-MQA DAC for conversion.
That DAC will cause time smearing due to the reconstruction filter it applies.
Like it does with non-MQA files.
If you have a DAC that offers MQA rendering and the master was at a sampling rate higher
than 96 kHz, the signal gets reconstructed to the original sampling frequency, even if
it is 384 kHz.
There also is a provision that corrects for the time smearing of that DAC.
But since every DAC has its own time smearing fingerprint, the compensation circuit has
to be specific for that type of DAC.
Therefore software like Roon and Tidal player can never perform this last step.
If you own a DAC that does both phases, you can even use normal - non MQA - player software
or hardware like JRiver, Volumio, Squeezebox, yes even Linn players to send a digital MQA
file to a DAC that does both the MQA core decoding and rendering.
You then get the same result as with core decoding software plus an MQA rendering DAC.
Of course with the limitations of the hardware used.
So there are three groups of DAC's: 1: Non-MQA DAC's
2: MQA rendering DAC's that need software to do the core decoder
3: MQA DAC's that do the core decoding and the rendering.
Hence there are four possibilities when playing an MQA file:
1: You have no MQA software or hardware: your can play MQA files as if they are normal 44.1
or 48 kHz files.
Time smearing in the recording is corrected, the time smearing in the DAC isn't.
2: You use player software that can do the MQA core decoding, like Tidal player or Roon,
and a non-MQA DAC: you get an audio signal at the original sampling rate of the master
up to 96 kHz.
That can be 44.1 kHz but also 96 kHz, depending on the original master.
Time smearing in the recording is compensated for but you don't get the time smearing
compensation appropriate for your DAC. 3: You use player software that can do the
MQA core decoding, like Tidal player or Roon, and a DAC that can't decode but can render
MQA signals: both the recording and your DAC are time compensated for so you get the best
quality an MQA file can offer on your equipment.
Examples of MQA rendering only DAC's are the AudioQuest DragonFly DAC's.
3: You use a DAC that is able to do both the MQA core decoding and rendering: Now your
source, being a hardware streamer, a cd-player or music player software on your computer
that doesn't need to be MQA enabled.
As long as it can send out a bit perfect digital signal to the MQA DAC, you will get the full
MQA quality up to 384 kHz sampling, provided the master was 384 kHz.
And both the recording and your DAC are being time compensated for.
Then about the cd-player: there are now MQA cd's as well, although I don't expect
this to become very popular.
Streamers that are MQA enabled internally normally have the core decoding done by its
processor inside the streamer and then send it through an MQA module to the DAC chip.
That MQA module is then optimised for that type of DAC chip.
This is why the digital output of streamers often output the core decoded signal, meaning
up to 96 kHz sampling.
Roon uses this to step approach to offer all kinds of digital signal processing.
Normally Roon sends out a bit perfect signal to the endpoint.
But the user can have the volume between tracks of albums levelled out automatically.
Or have equalisers applied to compensate for shortcomings in the stereo or acoustics.
It can even do sophisticated room connection using the impulse response of the room to
convolute a room corrected audio signal.
Before Roon became MQA compatible, using DSP techniques would cripple the MQA authentication
so you would end up with a 44.1 or 48 kHz signal.
But since version 1.5 Roon can not only do the core decoding but it can apply all kinds
of DSP functions while keeping the MQA authentication.
This means that rendering DAC's will do the normal MQA level rendering while full
MQA DAC's will recognise it receives an MQA Core signal and thus will switch to rendering
only.
So now room correction, cross fading and volume levelling all became possible.
MQA matters have been troubled somewhat by a loud minority that screamed hell and fury
but were very poorly informed.
It was rumoured that MQA is copy protected.
Wrong, there is NO copy protection in MQA.
There never was an there will never be.
I have this in writing from Bob Stuart, one of the two inventors.
If I would mail you an MQA file, you would perfectly be able to play it back.
Only the quality at which it will be played back depends on your equipment.
You can play it back on your phone, on the old 300 euro Stereo-in-a-Box system in the
kitchen that doesn't support MQA and on your super duper MQA enabled stereo in your
listening room.
Try that with a normal 96 kHz FLAC file.
Chances are the latter will only play in your listening room since the other two sets don't
do 96 kHz.
Another argument used agains MQA is that it is lossy, just like MP3.
Incorrect.
With MP3 sound quality over the entire audio band is willingly decreased to achieve smaller
file sizes.
MQA uses lossless compression up to 45 kHz bandwidth and uses a different way of storing
the information above 45 kHz.
Furthermore it uses bits that are not used for audio to store relevant information in.
Pure technically you could say that MQA is lossy above 45 kHz.
But there is no relevant information above 45 kHz, the only reason to use higher sampling
rates is to be able to use milder anti-aliasing and reconstruction filters.
See my video "Is MQA lossless".
There you will learn that when you consider the entire chain, MQA potentially looses even
less quality than normal PCM.
Yes, there is a loud minority - mainly in the computer audiophile community - that don't
like systems other than public domain.
But big steps - like MQA offers - can never be public domain.
It took Linux over 40 years to become more or less usable to the normal consumer.
Vinyl wasn't public domain, CD wasn't, SACD wasn't and so on.
If you are not sure about MQA, just listen to it.
If you don't hear an improvement, just stick to the gear you have.
And If you do hear an improvement, consider if it is worth the investment.
Inform yourself, decide for yourself and don't let the loud minority decide for you.
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I am Hans Beekhuyzen, thank you for watching and see you in the next show or on theHBproject.com.
And whatever you do, enjoy the music.
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