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AudioQuest adds MQA Support to Dragonflies via firmware

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11 minutes ago, citsur86 said:

So if you are using the Dragonfly Red or Black and having Tidal do the "core" unfold, and it sends the Dragonfly 96KHz, then what was the point of the update to the Dragonfly to make it able to do the second unfold if it can only go up to 96KHz?  

 

So that the DragonFly can do the second unfold and with the MQA libraries match the MQA Filter for that track inside the the ESS DAC chip.

 

Remember MQA is preserving the authenticity of the music. Think about it that way!

 

So if you are playing some 24/96 file in standard PCM format in XYZ file type (i.e. AIFF/WAV or FLAC/ALAC) then you get that in DragonFly using minimum phase filters built into the ESS DAC chip.

 

If you get an MQA file it will be unfolded on the host application delivered to the DragonFly over USB and inside the MQA code on the DragonFly it will be unfolded and presented to the ESS DAC chip with the Filter that matches the track.

 

Thanks,

Gordon

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8 minutes ago, mansr said:

The USB interface is limited to 96 kHz. Subsequent upsampling is done either by the microcontroller (which I doubt it has the CPU power for) or by the DAC chip itself using filter parameters specified by the MQA metadata.

Whatever the original sample rate, the MQA file contains true audio data only up to 48 kHz (and the 24-48 kHz band is heavily compressed). Anything above that is discarded at the encoding stage, and no amount of hand-waving can bring it back.

 

again, this is why we should not listen to people who speculate how things work. mansr, there is example upsampling code and libraries available for the MX processor. Even with MQA running we would be able to add another 256tap x2 (stereo) upsample if we wanted to. But that would just waste power, increase system noise and lower the overall quality of the experience.

 

Thanks,

Gordon

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25 minutes ago, abrxx said:

 

Sure. I'm just using the official MQA speak, or at least I thought I was!

 

Meridian says their Explorer 2 does three unfolds and to turn on MQA passthrough in Tidal.

Edited by DarwinOSX

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citsur86   

I found this article to be immensely helpful in understanding MQA.

 

Especially this part:

 

Software / Core Decoding

 

MQA is a whole host of processes and technologies, but for purposes of this civilian discussion, let's look at it as three processes. MQA files can be 1. Fully decoded, 2. Software / core decoded, and 3. Rendered. Software decoding is capable of exactly what its name suggests, decoding MQA. Rendering must be done in hardware because it is custom matched to the DAC system.

 

Software decoding, what MQA Ltd calls core decoding, provides what I consider to be about 90% of the MQA benefits. Decoding in software unfolds / unpacks the music to a maximum of twice the base sample rate, 88.2 or 96, for either analog or digital output.

 

EQ, bass management, and other non-MQA DSP can take place after core decoding.

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PeterSt   
1 hour ago, Wavelength said:

Also I am sure MQA would appreciate it if you would not prod questions like this.

 

Yes Gordon, and my biggest "con". But I have the idea you started this now.

 

E. There can be software decoding all right, but no filtering or whatever DSP is possible.

 

Say that I forgot that option. O.o Actually I forgot it because it is too obvious that anno 2017 such means are more or less a requirement.

So you see, this renders our MQA decoding software useless (which is for 50% about its filtering) and this also renders our Phasure DAC useless, which is NOS and with the assumption that NOS DACs require filtering of any kind (call me strange).

 

So here I am ... XXHighEnd (Windows) decodes MQA but no MQA rendering is possible behind it. Far away with the option that a NOS DAC stays that (NOS instead of MQA filtering), but it always requires the software to pass through. But see my little list :

 

 

MQA Decoding software with nice filter -> MQA Rendering DAC <- Impossible.

 

MQA Decoding software with volume control -> MQA Rendering DAC without VC possibilities (no VC anywhere) <- impossible.

 

MQA Decoding software with nice filter and VC and DSP and what not -> Non-MQA rendering DAC <- Possible but moot because software can't run on MQA DAC.

 

MQA Decoding software without any processing -> MQA Rendering DAC <- Possible but no market (not any more and of course my subjective opinion).

 

Non-MQA Decoding software  -> MQA Decoding DAC without rendering <- Possible but probably not allowed by MQA (didn't investigate that). Is moot anyway.

 

Non-MQA Decoding software without filtering or other means of VC and DSP  -> MQA Decoding and Rendering DAC <- Possible. But no market these days.

 

Non-MQA decoding software with filter or VC/DSP -> MQA Decoding and Rendering DAC <- White light.

 

MQA Decoding software with VC which controls in-DAC VC -> MQA Rendering DAC <- Possible and maybe there is a market for this. This should be the way the DF works.

 

MQA Decoding software with VC which controls in-DAC VC -> MQA Decoding and Rendering DAC <- Possible and maybe there is a market for this.

 

 

Regarding the last option, I am not so sure whether it is possible that such a DAC optionally will be able to bypass the MQA Decoding stage. I mean, who depicts that such a DAC will have this option. So if not, said software will be useless again and it depends on the DAC it runs into.

 

 

I don't think this is information which can harm MQA and it is the truth of functional outcome anyway. Besides that it is clear that readers mostly lack this knowledge, so I hope this helps someone.

A lot is about the lack of a pre-amp or other means of analogue volume control. So if I refuse to use such a (in my view) detrimental means of VC, I am completely stuck from various angles. But it is the combination of everything (see list above).

Thus believe it or not - I have everything running here, also the hardware. But because of the lack (or my refusal) of using a pre-amp, I G-D never heard one note of full fletched MQA (meaning : I can't use the renderer part or else I lack the VC or the filtering or whatever I do and like to do in software).

 

Thanks for listening,

Peter

 

Edit :

PS: If my list is wrong or incomplete, I have to apologize. But let's make it correct then. Thanks.

Edited by PeterSt

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mansr   
10 minutes ago, PeterSt said:

MQA Decoding software with volume control -> MQA Rendering DAC without VC possibilities (no VC anywhere) <- impossible.

The metadata in the decoded stream sent to the renderer includes a gain parameter. If this is set, the renderer applies software volume control. I don't know if this capability is a hard requirement or if MQA would certify a renderer that ignored it.

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PeterSt   
5 minutes ago, mansr said:

The metadata in the decoded stream sent to the renderer includes a gain parameter. If this is set, the renderer applies software volume control. I don't know if this capability is a hard requirement or if MQA would certify a renderer that ignored it.

 

That would be this option :

 

18 minutes ago, PeterSt said:

MQA Decoding software with VC which controls in-DAC VC -> MQA Rendering DAC <- Possible and maybe there is a market for this. This should be the way the DF works.

 

As far as I know this is optional. But easy to be wrong.

Edited by PeterSt

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10 minutes ago, PeterSt said:

 

Yes Gordon, and my biggest "con". But I have the idea you started this now.

 

E. There can be software decoding all right, but no filtering or whatever DSP is possible.

 

Say that I forgot that option. O.o Actually I forgot it because it is too obvious that anno 2017 such means are more or less a requirement.

So you see, this renders our MQA decoding software useless (which is for 50% about its filtering) and this also renders our Phasure DAC useless, which is NOS and with the assumption that NOS DACs require filtering of any kind (call me strange).

 

So here I am ... XXHighEnd (Windows) decodes MQA but no MQA rendering is possible behind it. Far away with the option that a NOS DAC stays that (NOS instead of MQA filtering), but it always requires the software to pass through. But see my little list :

 

 

MQA Decoding software with nice filter -> MQA Rendering DAC <- Impossible.

 

MQA Decoding software with volume control -> MQA Rendering DAC without VC possibilities (no VC anywhere) <- impossible.

 

MQA Decoding software with nice filter and VC and DSP and what not -> Non-MQA rendering DAC <- Possible but moot because software can't run on MQA DAC.

 

MQA Decoding software without any processing -> MQA Rendering DAC <- Possible but no market (not any more and of course my subjective opinion).

 

Non-MQA Decoding software  -> MQA Decoding DAC without rendering <- Possible but probably not allowed by MQA (didn't investigate that). Is moot anyway.

 

Non-MQA Decoding software without filtering or other means of VC and DSP  -> MQA Decoding and Rendering DAC <- Possible. But no market these days.

 

Non-MQA decoding software with filter or VC/DSP -> MQA Decoding and Rendering DAC <- White light.

 

MQA Decoding software with VC which controls in-DAC VC -> MQA Rendering DAC <- Possible and maybe there is a market for this. This should be the way the DF works.

 

MQA Decoding software with VC which controls in-DAC VC -> MQA Decoding and Rendering DAC <- Possible and maybe there is a market for this.

 

 

Regarding the last option, I am not so sure whether it is possible that such a DAC optionally will be able to bypass the MQA Decoding stage. I mean, who depicts that such a DAC will have this option. So if not, said software will be useless again and it depends on the DAC it runs into.

 

 

I don't think this is information which can harm MQA and it is the truth of functional outcome anyway. Besides that it is clear that readers mostly lack this knowledge, so I hope this helps someone.

A lot is about the lack of a pre-amp or other means of analogue volume control. So if I refuse to use such a (in my view) detrimental means of VC, I am completely stuck from various angles. But it is the combination of everything (see list above).

Thus believe it or not - I have everything running here, also the hardware. But because of the lack (or my refusal) of using a pre-amp, I G-D never heard one note of full fletched MQA (meaning : I can't use the renderer part or else I lack the VC or the filtering or whatever I do and like to do in software).

 

Thanks for listening,

Peter

 

Edit :

PS: If my list is wrong or incomplete, I have to apologize. But let's make it correct then. Thanks.

Peter,

 

I make NOS DACS as well. I will probably not put MQA on them. They are what they are and stand alone in the way they sound. Sure you can still play MQA tracks on them as you can with other DACS that don't have MQA support.

 

E? I am a little confused... I take it your talking about DSP filtering before it hits the DAC or between the render application and an MQA capable DAC and the interface (USB, other).

 

Correct that or digital volume will manipulate the data and not create an MQA bit true stream to the product and will render the MQA non-compliant.

 

Peter, you can design into your product analog volume controls like others and myself have done and over endpoint 0 have a system wide volume control. There are many ways to do that actively and passively.

 

Peter, you could also entertain having digital filters and a NOS DAC. Remember digital filters were originally conceived for Low Pass to remove all the unwanted crap. But remember MQA might be using Filters that are not of that type. They might be for other areas of the listening area. I really don't know this to be true but this is very possible. It would not effect the NOS nature of your product and you still could be MQA compliant.

 

Your in control of your products. If you wanted to do MQA, I would talk to them and see what they have to say.

 

Thanks,

Gordon

 

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PeterSt   

Gordon, thank you for a kind reply.

 

4 minutes ago, Wavelength said:

E? I am a little confused... I take it your talking about DSP filtering before it hits the DAC or between the render application and an MQA capable DAC and the interface (

 

The former.

The latter is a bit difficult to judge as you call it "render application" (haha). Anyway, the DSP etc. can also be in-DAC, but this is not my stihl hence I regard this "old fashioned". In-software is the way to go - is more flexible as well (just a strategy).

 

7 minutes ago, Wavelength said:

Peter, you can design into your product analog volume controls like others and myself have done and over endpoint 0 have a system wide volume control. There are many ways to do that actively and passive

 

Sure ! But in my view there's one good way only, and this requires another DAC (chip) setup.

At this moment I like to continue the NOS1a DAC.

(I have suitable designs with voltage control, but they are not exactly NOS as such (but SDM based)

 

9 minutes ago, Wavelength said:

Peter, you could also entertain having digital filters and a NOS DAC. Remember digital filters were originally conceived for Low Pass to remove all the unwanted crap. But remember MQA might be using Filters that are not of that typ

 

Gordon, yes. And they can be in the MQA compliant DAC just as the (standard) filters in there can be bypassed all together.

And now I like a code example ...

 

11 minutes ago, Wavelength said:

If you wanted to do MQA, I would talk to them and see what they have to say.

 

I can be the most wrong, but I think MQA never had the situation and question at hand other than from me.

So what I want / need, for sure can be done (but it is a bit of digging).

I now need to emphasize that I don't expect the people from MQA to give this small boy any priority over the big players, although it starts to look like I currently have the only MQA capable player for Windows (Tidal or offline). Anyway, I hate to give reminders to people who for sure are busy enough before they have some spare time to investigate how to actually use the API regarding this. But as said, I can be wrong (but don't have the answer anyway) and maybe I should give them a call again. Or spend more time on it which I am always in lack of ...

 

Regards and thanks for the heads up,

Peter

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7 minutes ago, PeterSt said:

 

 

Peter,

 

Quote

Sure ! But in my view there's one good way only, and this requires another DAC (chip) setup.

At this moment I like to continue the NOS1a DAC.

(I have suitable designs with voltage control, but they are not exactly NOS as such (but SDM based

 

You don't need another DAC chip to do this. There are several ways after your NOS DAC chip to do volume. Like what I do is put the volume control between the DAC output analog domain and the output section. Usually in my case a Tube Buffer or transformer coupled tube section.

 

Quote

I now need to emphasize that I don't expect the people from MQA to give this small boy any priority over the big players, although it starts to look like I currently have the only MQA capable player for Windows (Tidal or offline). Anyway, I hate to give reminders to people who for sure are busy enough before they have some spare time to investigate how to actually use the API regarding this. But as said, I can be wrong (but don't have the answer anyway) and maybe I should give them a call again. Or spend more time on it which I am always in lack of ...

 

Peter won't know unless you try.

 

Thanks,

Gordon

 

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crenca   
3 hours ago, Wavelength said:

 

Peter,

 

Really go troll somewhere else.

 

~~~

 

I am under NDA as anyone would be working with MQA.

 

I am not an employee of AudioQuest. I am a hired designer, like I do with the other 18 companies I do work for including Ayre, Berkeley, MBL...

 

crenca, Why do you follow guys like mansr? You know if he is so great then why is he wasting time trying to reverse engineer and put down MQA. Why isn't he out there making a product that is better than all of this? Why because he probably can't and if he can, great it would lend credibility to who ever he is.

 

All this bickering about "HOW" MQA works is useless. The main reason is that you have no idea what is done on the file side of things. What and how the files are encoded and what actually is in the format. Oh sure you can sit around and think as any engineer would about the possibilities. But to truly know what's going on is creating misinformation.

 

Look I say if you don't have a DragonFly, you shouldn't even be on this thread.

 

I have pretty much laid out how it works on the DragonFly, probably more than I should have. If you having issues or want to know how to set it up and stuff then I would be happy to answer it. Or if you are having problems I can help you out.

 

I am not getting paid for this, I am not a spokesperson for AudioQuest or MQA. I am just an engineer who has been programming my whole life. My bio is pretty well known... I designed PC's for a living (540K last count), wrote BIOS code in assembler, developed IC for communications (Ethernet, Token Ring, USB, 802.11 bridges). I left the six largest hardware software company as the Chief Engineer to work on my passion in Audio. Well that and I had 2 Class A products in Stereophile and received product of the year in Absolute Sound. Two jobs was one too many and I had other products to finish like dual DSP SPDIF DACs, preamps and yea even speakers. I have designed and worked on and sold over 165 products since then. It's been a lot of fun...

 

But really posts like this are just too disturbing. It really doesn't make any sense Peter why you even say things like this. It's one of the reasons I don't frequent here more often.

 

Thanks,
Gordon

 

 

Gordon,

 

You have answered some of the question of substance today - thanks!

 

Why we follow guys like mansr is because they are the yin to your yang.  Your yang is the slightly (or more) manic, ambitious, successful, take-no-prisoners engineer.  You are proud of your products and success (with good reason) but you think the rest of us should be really really really impressed.  In a sense we are, but then it is YOUR success and it is only of value to us to the extent that it helps us.  To state the obvious, your self interest does not necessarily align with ours. 

 

What is "disturbing" is your myopic vision around MQA.  You don't appear to understand the industry and market motivations for its adoption, and if you do you don't seem to care how this effects the consumer.  MQA just might be a real advancement in the SQ dept (I readily admit that it is too some extant - though so far it is way over-sold).  MQA-in-Dragonflies/etc. might be a real engineering success on your part and another notch on your gun - congratulations.  MQA is also a DRM Trojan designed to fundamentally change the consumers musical digital ecosystem at the root (i.e. format) level.  You and many others are "ok" with that, but many consumers are not and we are able to see through the obfuscations of MQA.  When you repeat those obfuscations or attack our attempt to identify and characterize certain facts of MQA and its implementation(s) as "misinformation" then all your engineering success and mojo counts for nothing.  At that point you are in Bob's world - the world of the Big Fat Liar.  

 

You have stepped back from this a bit today, even admitting what you do not know (though you might but are forced into such "white lies" by the NDA).  I would urge caution on your part - MQA forces you into a social context in a way your previous engineering work probably has not.  MQA is not just another encoding, nor is it an audio product like any other audio product.  It is a legal entity at the root of our digital musical lives, and it's IP nature and DRM reality (it IS DRM in it's current form v. 1.2).  We the consumer ARE going to look at, evaluate, and discuss this aspect as well.  We will not be duped into looking at it as just another engineered product - which is to say we will not just shut up and listen...

 

 

 

 

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1 hour ago, revand said:

Does this mean that the Dragonfly Red/Black at making the second unfold of the music file already unfolded by the desktop app or Audirvana Plus 3 to 24bit/88.2 or 24bit/96 kHz (at "rendering") cannot provide the resolution of the original master?

Strictly speaking, the resolution of a 384KHz master was long lost in the folding... Even if you had a 24bit/96KHz master, once you fold it to 24bit/48KHz you cannot get back the original data. MQA Co. argues it is "perceptually lossless" meaning that the unfolded file (48KHz back to 96KHz) is "psychoacoustically indistinguishable" from the original 24/96. I will leave it to you to judge what that means.

 

The second step in decoding is the application of filters to render the file. This is at best "informed upsampling". Consider the Dragonfly's ESS DAC: It does not know anything about MQA, all it does know is to set specific upsampling filters as instructed by the microcontroller.

 

So when someone says "recreating the original" or some BS like this, I just roll my eyes...

 

Does it sound good? Sure. Does it prevent you from using room corrections? Yes. Does MQA sound better than PCM with room corrections? For those that enjoy the latter the answer is clearly no.

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14 minutes ago, miguelito said:

Strictly speaking, the resolution of a 384KHz master was long lost in the folding...

 

Lost or slightly diminished?

You are never going to get PCM streaming which means it will always be an outlier used by people who read forums like this one.

Edited by DarwinOSX

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PeterSt   
5 minutes ago, miguelito said:

Consider the Dragonfly's ESS DAC: It does not know anything about MQA, all it does know is to set specific upsampling filters as instructed by the microcontroller.

 

You must be a bit careful with this ...

As I understand, the DF doesn't go beyond 96KHz anyway, so there is not much to upsample, assumed the original file was 96KHz (or 88KHz).

This, while upsampling is also a possibility (by MQA hardware). But I think this is completely outside the subject.

 

To be hopefully more clear : the "upsampling filters" as you mention them are nothing of the kind when we'd talk about reconstructing the native 96KHz (etc.). Let's call that "unfolding process" and you're at what it is.

And this works up to 384KHz (or 352.8 more practically (DXD like from 2L).

 

I could also say : the filtering which can be disengaged (in-DAC) can be externally controlled. This is something very different from adding our own filtering (which is upsampling at any event !) in-DAC. Envision that I talked in this realm when I said "replace the MQA filters by our own" (similar). Thus :

 

MQA Renderer (is in-DAC) -> Our digital Filter -> D/A Output.

 

which would be very similar and more easy to understand :

 

MQA Renderer (is in-DAC) -> Our digital Filter chip -> D/A Output.

 

... because that already feels fairly normal.

But in "modern days" we don't like to approach it like that because we go for option A the least, and actually better like the HQP / XXHighEnd solution which is in-PC. And now nothing works ...

UNLESS in-PC the rendering can be done.

Tadaaa ... (for those who adhere MQA)

 

 

 

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6 minutes ago, PeterSt said:

 

You must be a bit careful with this ...

As I understand, the DF doesn't go beyond 96KHz anyway, so there is not much to upsample, assumed the original file was 96KHz (or 88KHz).

This, while upsampling is also a possibility (by MQA hardware). But I think this is completely outside the subject.

The 2L recordings go to 88KHz (first unfold) into the DF and get upsampled to 352KHz in the DF's ESS DAC.

 

Quote

To be hopefully more clear : the "upsampling filters" as you mention them are nothing of the kind when we'd talk about reconstructing the native 96KHz (etc.). Let's call that "unfolding process" and you're at what it is.

And this works up to 384KHz (or 352.8 more practically (DXD like from 2L).

88 or 96 to 352 or 384 is upsampling in the ESS DAC. The MQA embedded data that the microcontroller decodes tells the ESS DAC what upsampling settings/filter to use. There are no MQA owned anything in that DAC.

Edited by miguelito

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10 minutes ago, DarwinOSX said:

Lost or slightly diminished?

You are never going to get PCM streaming which means it will always be an outlier used by people who read forums like this one.

Lost in the mathematical sense. Once you allow for "psychoacoustically equivalent" you're doing medical perception not scientifically verifiable facts.

Edited by miguelito

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12 minutes ago, miguelito said:

Lost in the mathematical sense. Once you allow for "psychoacoustically equivalent" you're doing medical perception not scientifically verifiable facts.

 

Lost seems overstated to me including in the mathematical sense.

Psychoacoustics is definetly perception and that can differ greatly of course.

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PeterSt   
13 minutes ago, miguelito said:

88 or 96 to 352 or 384 is upsampling in the ESS DAC. The MQA embedded data that the microcontroller decodes tells the ESS DAC what upsampling settings/filter to use. There are no MQA owned anything in that DAC.

 

Maybe I am unsure what you mean by the latter ("owned") ? language problem ...

If you only know that MQA can unfold to 384 when the file natively is that.

Uhm ... don't ask me how that would work when still the transport (stream) is 44.1 or 48 but it is a typical thing I take for granted. Anyway it is not upsampled.

This, while upsampling to max 384 is a feature of MQA.

 

I suppose you are saying that the DF just doesn't go beyond 96. Fine. But this is not related to MQA's capabilities (and upsampling as such I don't call a capability to begin with, but alas, it can do that too).

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Just now, mansr said:

0-24 kHz: mostly preserved

24-48 kHz: heavily compressed

48-inf kHz: completely lost

 

Thanks.

I have a Meridian Explorer 2 and and am trying to compare it to what I am reading here.

I understand that not all MQA is the same also.

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22 minutes ago, PeterSt said:

 

What do you mean by that ?

If it is what I think, I wouldn't put money on it ... ¬¬

I mean no streaming service is going to adopt PCM as a format.

MQA's major advantage besides sound is that at least one streaming service has adopted and there are rumors of others doing so.

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PeterSt   
5 minutes ago, DarwinOSX said:

Psychoacoustics is definetly perception and that can differ greatly of course.

 

If we only (all of us !) could count that out ...

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1 minute ago, PeterSt said:

 

Still unsure what you are trying to tell.

MQA is PCM ...

PCM as PCM is to people who use it currently with PCM Dacs etc.

What is typical PCM file size?

Edited by DarwinOSX

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