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MQA, where is decoding done, what is required?

Jimbob54

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You
I would really not buy a CCA for Tidal no matter how convenient it may be.

I would do Roon or DLNA (with a raspberry pi).
You won't by a CCA full stop. Not easily anyway. Discontinued!
 

abdo123

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With a topping D90 MQA, there should be a chip in front of the AK4499, in which the MQA

Yes the XMOS USB chip does the first unfold, and a chip in the middle between the DAC chip and the XMOS chip does the second unfold.

With Gustard X16 the second unfold is integrated into the DAC chip itself. Which might be a trend soon.
 

Beershaun

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Sorry OP. I thought your question had previously been answered.

You want to know if your Pioneer does the full unfold of MQA or just the first unfold. What information can you give us about the file it's playing when it's playing MQA? One way you can tell if it's only doing the first unfold or the full unfolding is the sample rate information. If you have an MQA file that is 96khz or higher then it will need to do the full unfolding to play at that rate. If it's only doing the first unfolding you will be limited to 44khz or 48khz.

Do you have a way to see what sample rate your device is playing at?

Use @danadam link to download an MQA file and load it onto your player and see what it plays.
 

Vincentponcet

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MQA is an encoding format. It should be possible to have a software MQA decoder, and make the full decoding for any DAC.
There will be licensing issues, but look at ffmpeg, they do dolby digital / trueHD and DTS / HD-MA decoding.
At some point, MQA will be reverse engineered.
Anyway, FLAC is better.
 

Jimbob54

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Unfortunately, I still can't tell at which point MQA is decoded in a DAC if the DAC chip does not contain an MQA branch.

As an an example:
With a topping D90 MQA, there should be a chip in front of the AK4499, in which the MQA decoding takes place.
1. Does the topping D90 fully unfold MQA? Or only partially?
2. Is this chip a special IC from MQA, or simply a processor with software from MQA?

I also own a Pioneer XDP-30R which supposedly can "MQA".
This MQA function was subsequently added through a firmware update.
Unfortunately, I can't find any information about whether this MGA function is fully developed or only halfway.

How do I know how far the MQA function / implementation goes with a device?

For the D90 mqa it's the xmos USB chip that is mqa enabled (I believe) and is a full decoder. The non mqa version has different xmos USB chip.
 

Vincentponcet

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Yeah I am curious to understand if an MQA file itself is truly backward compatible and can be sent to a DAC that only knows and decodes FLAC. I'll see if I can buy an MQA file and test to see if I can stream it to my CCA via PLEX which explicitly doesn't know about MQA.

DAC does not "know" FLAC. They receive PCM (or DSD).

if it is truly backward compatible then I can see why Tidal would want to go full MQA for everything. It makes their life MUCH simpler to just send one file no matter what the device is and the file figures it out. Also it' supposed to be a smaller size file so it's better for customers who are paying for data as well as reduces their data costs. Win-Win for them.

Tidal offers 4 bitrates, not one.
https://support.tidal.com/hc/en-us/articles/360002599997-What-Audio-Quality-Does-TIDAL-HiFi-Offer-
 

Glasvegas

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I would really not buy a CCA for Tidal no matter how convenient it may be.

I would do Roon or DLNA (with a raspberry pi).

Problem is every other method is a poor second to casting from the native Tidal app.
 

Beershaun

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@Roland68 responded with an additional question about their specific portable audio player. Let's bring the thread back to helping the OP answer their question about the capabilities of their pioneer DAP.
 

Jimbob54

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Yes, of course. But not many devices have that option.
If I had my time again, I would have got an RME dac (for eq) and strapped a CCA to it and had done.
 

Jimbob54

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Unfortunately, I still can't tell at which point MQA is decoded in a DAC if the DAC chip does not contain an MQA branch.

As an an example:
With a topping D90 MQA, there should be a chip in front of the AK4499, in which the MQA decoding takes place.
1. Does the topping D90 fully unfold MQA? Or only partially?
2. Is this chip a special IC from MQA, or simply a processor with software from MQA?

I also own a Pioneer XDP-30R which supposedly can "MQA".
This MQA function was subsequently added through a firmware update.
Unfortunately, I can't find any information about whether this MGA function is fully developed or only halfway.

How do I know how far the MQA function / implementation goes with a device?
As for the pioneer, there should be "the lights" for which mqa is famous. On the display there will be some indication of what level you're getting. If you see 192 kHz, definitely full decode. Blue light I think means same
 

Zensō

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Just to add another data point to the discussion, here’s Roon doing the first unfold and sending a 96 kHz file to my RME. The display on the DAC confirms it’s receiving a 96 kHz stream.

FB0E4AC3-F9A7-449B-80C2-75FB34C0A0BF.jpeg
 
Last edited:

levimax

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After reading about MQA I decided to drop Tidal and switch to Qobuz and am MUCH happier not having to worry about buying a new MQA DAC..... I also save $8 per month. I think it is safe to say that higher sampling rates or bit depth are not going to make much of any difference (I say none based on my ABX testing) but different mastering's do sound different. For what it's worth I compared Original LP, Original CD, to the Tidal "master" for a couple of songs using "frequency analysis" after equalizing the levels. For "Sultans of Swing" I even had the previous non MQA Tidal version to compare. In both cases the Tidal MQA (with one unfold) definitely had different mastering's and I could ABX it against the other versions.
Sultans of swing.jpg
I.G.Y.  3 ways.jpg
 

Jimbob54

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After reading about MQA I decided to drop Tidal and switch to Qobuz and am MUCH happier not having to worry about buying a new MQA DAC..... I also save $8 per month. I think it is safe to say that higher sampling rates or bit depth are not going to make much of any difference (I say none based on my ABX testing) but different mastering's do sound different. For what it's worth I compared Original LP, Original CD, to the Tidal "master" for a couple of songs using "frequency analysis" after equalizing the levels. For "Sultans of Swing" I even had the previous non MQA Tidal version to compare. In both cases the Tidal MQA (with one unfold) definitely had different mastering's and I could ABX it against the other versions. View attachment 102268View attachment 102269
Wow, that 10db difference at 3k between the 2 tidal versions in the first chart. Then wtf in the second.
 

Vincentponcet

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MQA is not one single bit rate (or sample rate /bit depth). Which just adds to confusion.
MQA presents itself as PCM 24/48, so one bitrate.

wikipedia said:
Given the low amount of energy expected in higher frequencies, and using only one extra frequency band layer (upper 44.1 kHz band of 96/24 packed into dither of 48/16) and one touchup stream (compressed difference between original 96/24 and 48/16) are together distributed as a 48/24 stream, of which 48/16 bit-decimated part can be played by normal 48/16 playback equipment.
 

Jimbob54

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MQA presents itself as PCM 24/48, so one bitrate.
But when decoded its either 44. 1, 48, 88.2, 96, 192 etc. That's the numbers the end user is being conditioned to care about. That, and the coloured lights.
 
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