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AudioQuest adds MQA Support to Dragonflies via firmware

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9 minutes ago, PeterSt said:

 

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

What I mean is that there is no knowledge of how to unfold MQA in the ESS DAC. My understanding it that the firmware update for the Dragonfly only touches the microcontroller code, not the ESS DAC firmware. Maybe @Wavelength can clarify.

 

Quote

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.

You're taking too many things for granted, methinks... :)

 

Quote

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).

No. What I am saying is in fact EVERY renderer will start from a 88 or 96 KHz stream. I have seen nothing in the MQA documentation that negates that the first 2x unfold is ALWAYS done in the same exact way, be it exclusively in hardware or split between a software unfold and a further rendering.

 

So in other words, MQA is ALWAYS decoded in two steps:

1- Unfold to 2x rate

2- Post-process to target rate

 

If I missed docs that indicate I am wrong, please point me. Thank you.

Edited by miguelito

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PeterSt   
3 minutes ago, DarwinOSX said:

What is typical PCM file size?

 

For streaming ? does not matter. For bandwidth, yes. But bandwidth is no problem either. And if not today, then tomorrow.

Anyway, what I was suggesting is that even 384 wouldn't be a problem. But it depends on the software ...

B|

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mansr   
2 minutes ago, miguelito said:

So in other words, MQA is ALWAYS decoded in two steps:

1- Unfold to 2x rate

2- Post-process to target rate

This is what the MQA software does and how the format is designed. If some document claims otherwise, it is wrong.

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PeterSt   
5 minutes ago, miguelito said:

So in other words, MQA is ALWAYS decoded in two steps:

1- Unfold to 2x rate

2- Post-process to target rate

 

Completely correct. But this doesn't mean that #2 is upsampling.

Upsampling = fake. And this is not what MQA provocates (same as a native 96 file which is unfolded to that, taking distance from how lossy that is or not). OK ?

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PeterSt   
7 minutes ago, miguelito said:

You're taking too many things for granted, methinks... :)

 

Haha no. I am trying to utilize all the diplomacy my father ever put into me. But I am not much used to that (as people may know). I am dutch as well, so that's an extra handicap.

 

LOL

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5 minutes ago, PeterSt said:

 

For streaming ? does not matter. For bandwidth, yes. But bandwidth is no problem either. And if not today, then tomorrow.

Anyway, what I was suggesting is that even 384 wouldn't be a problem. But it depends on the software ...

B|

 

5 minutes ago, PeterSt said:

 

For streaming ? does not matter. For bandwidth, yes. But bandwidth is no problem either. And if not today, then tomorrow.

Anyway, what I was suggesting is that even 384 wouldn't be a problem. But it depends on the software ...

B|

Streaming at home does not matter for people with robust wifi and bandwidth.  

Streaming via a carrier matters for data usage, bandwidth, and performance. i.e. no stuttering.

We all know this.

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mansr   
1 minute ago, PeterSt said:

Completely correct. But this doesn't mean that #2 is upsampling.

It wouldn't have to be, but it is.

1 minute ago, PeterSt said:

Upsampling = fake. And this is not what MQA provocates (same as a native 96 file which is unfolded to that, taking distance from how lossy that is or not). OK ?

No matter what MQA tries to claim, "rendering" to higher sample rates than 96 kHz is upsampling. Because of the leaky filters used, the upsampled signals contains strong images of the 0-48 kHz frequencies which might be mistaken for restored content. The original high frequency-content is simply not stored anywhere in the file, so there is no way to reconstruct it.

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4 minutes ago, mansr said:

This is what the MQA software does and how the format is designed. If some document claims otherwise, it is wrong.

 

Bob Stuart talks about three unfolds.

 

 

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abrxx   
3 minutes ago, mansr said:

I don't care what he talks about. It's nowhere to be seen in the actual software.

 

Yes it is. He's just using the same marketing language ("folds") for completely different things. Whether its un-encapsulating the 48/24 to 96/24, or the MQA-secret-sauce upsampling, he calls both unfolding. Additionally, each time the rate doubles, its an unfold. So to go from 48/24 to 192/24 is TWO unfolds. And so on....

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PeterSt   
12 minutes ago, DarwinOSX said:

Streaming via a carrier matters for data usage, bandwidth, and performance. i.e. no stuttering.

We all know this.

 

Of course. But it will disappear (any modern world will make it flat-fee).

And the no-stuttering ... ah, it is something I can guarantee (at any low bandwidth). But never mind, you point is clear.

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Peter,

Quote

Completely correct. But this doesn't mean that #2 is upsampling.

 

Thanks, this is exactly what I have been saying!

 

mansr, really you can look at the code all you want, your only getting 1/2 the picture without knowing what they are doing on the master side of this. Plus what we are doing on DragonFly may have nothing to do with what you have seen or reverse engineered.

 

miguelito, It's impossible to update the firmware in the ESS DAC chip that would require a metal revision. Everything we do is in our code. Also again, non of the unfolding is done in the DAC chip.

 

All,

Hey it's been great here for the most part. I am going to leave now. I have some guitar amps to build, finish up a tube DI + optical compressor and some other projects for Barenaked Ladies, Tom Tom Club, XTC and Melodime.

 

Thanks,

Gordon

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PeterSt   
12 minutes ago, mansr said:

The original high frequency-content is simply not stored anywhere in the file, so there is no way to reconstruct it

 

And you think that for 96 it is ?

(you can respond of course, but I'd have to stop right here)

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mansr   
6 minutes ago, abrxx said:

Yes it is. He's just using the same marketing language ("folds") for completely different things. Whether its un-encapsulating the 48/24 to 96/24, or the MQA-secret-sauce upsampling, he calls both unfolding. Additionally, each time the rate doubles, its an unfold. So to go from 48/24 to 192/24 is TWO unfolds. And so on....

MQA's own "rendering" code can upsample by 2x or 4x in a single step. If they want to call a 4x upsampling "two unfolds," so be it.

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PeterSt   
6 minutes ago, Wavelength said:

Hey it's been great here for the most part. I am going to leave now.

 

Gordon, let me be honest ...

 

No matter the way I challenged you, for me this felt back to 2008. An eventually civilized conversation with respect. I am not even talking about myself. But it seems to be as easy to join as the other POS.

(just invented that one, so guess)

 

Regards,

Peter

 

 

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mansr   
2 minutes ago, PeterSt said:

And you think that for 96 it is ?

The 24-48 kHz band is compressed and stored in the low 8 bits of the MQA 24-bit stream. As long as there isn't too much going on at those frequencies, it does a decent job of it, but there's obviously some limit to how much it can squeeze into that space.

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On 1/12/2017 at 3:19 AM, Ajax said:

 

Hi Miguelito.

 

Funny you should ask.

 

Two nights ago I selected several albums using the Tidal - "What's New / Masters" selection process on my MAC Air and checked the "passthrough" selection for my Explorer2 DAC. Under both checked and unchecked the blue light on my explorer did NOT come on as it is supposed to - it simply showed as a white light.

 

Not sure what is going on as I do not pretend to be a technical guru. If anyone could shed some "light" on what I could possibly be doing wrong it would be appreciated.

 

I will say that MQA aside this is a seriously competent DAC - sounds great. Below is a review from Australian HiFi, which I pretty much agree with, check the reference to MQA. Note the price quoted is in AUS$ but even taking the exchange rate into account you can see how we get ripped of here. I bought mine as a demo in England last May for GBP180. I think it sells for around US$300 in the states.

 

Not a lot of money to stick your toe into the MQA water as it plays very well without as a desktop or second room DAC.

 

Australian HiFi - Explorer2 DAC.jpg

 

All the best,

 

Ajax

Australian HiFi - Explorer2 DAC.jpg

 

The price in the U.S. is now $199.  It used to be $300.

Edited by DarwinOSX

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abrxx   

For those saying that MQA doesn't upsample (or downsample), it might be worth looking at what Bob actually wrote in his patent application for the "rendering" part of the process:

 

https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=WO&NR=2014108677A1&KC=A1&FT=D&ND=3&date=20140717&DB=EPODOC&locale=en_EP

 

Remember, MQA has many different parts, and the above patent only describes one part of the machine.

 

Thanks,

Alastair

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39 minutes ago, PeterSt said:

 

Of course. But it will disappear (any modern world will make it flat-fee).

And the no-stuttering ... ah, it is something I can guarantee (at any low bandwidth). But never mind, you point is clear.

 

We are talking about now. Not eventually.  

I get stutters and passes streaming on Tidal via LTE.

But I can see that it is important for you to be right to the point of being purposefully obtuse.

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46 minutes ago, abrxx said:

 

Yes it is. He's just using the same marketing language ("folds") for completely different things. Whether its un-encapsulating the 48/24 to 96/24, or the MQA-secret-sauce upsampling, he calls both unfolding. Additionally, each time the rate doubles, its an unfold. So to go from 48/24 to 192/24 is TWO unfolds. And so on....

But that's my point... The ESS DAC in the DF doesn't know anything about these unfolds. It only knows about upsampling. I acknowledge there's an interesting twist in choosing upsampling filters on a per-file basis, but lets not call it what it is not.

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Gonzbull   
On 5/22/2017 at 11:24 PM, miguelito said:

For sure mikes are used! I meant to say the simplistic picture of one mike to one pre to one ADC to the digital file is deceitful. In reality, many different mikes, to many different pres, to many ADCs, to a mixing console, to a digital master is more like it. Correcting the signature of a recording change, as MQA likes to picture it, is not a possible situation for most recordings.

Yup you are right about the many mics, pres, etc. But multiple mics have been used for recording since the beginning. Different mics and Pres are used to add character and to get the best out of the source. It would be like painting in primary colours otherwise. To that effect there's also different instruments and amplifiers and vocal chords that are used to make music. 

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mansr   
1 hour ago, Gonzbull said:

Yup you are right about the many mics, pres, etc. But multiple mics have been used for recording since the beginning. Different mics and Pres are used to add character and to get the best out of the source. It would be like painting in primary colours otherwise.

That's one way of doing it. There are also excellent recordings done with a single stereo pair.

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Gonzbull   
3 minutes ago, mansr said:

That's one way of doing it. There are also excellent recordings done with a single stereo pair.

 Yup your right. The majority of my favourite classical recordings were done with a stereo pair. The location plays a massive part in these recordings. Not so much with close miced which is most of what we get now. 

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