[ecwl]

I have to say I find the MQA remastering of old recordings, particularly old digital recordings a little suspect. I don't know where their white paper is on the process so I'm speculating and maybe completely biased and wrong. But from the sounds of it, what they're doing is to take a digital 16/44 master, run it through a million taps to reconstruct a 24/352 master (so a super high-end upsampling you can call it), maybe do some EQ to compensate for other digital recording issues, and then compress that 24/352 back into 16/44 which is the encoding part of MQA. So if you have MQA playback, you're playing back the 24/352 which is easier to handle and sounds better for most DACs than the 16/44 version due to limited tap length.
 
As for the compression part, I do think that's very clever. You take a 24/352 recording although most of the information is in the 24/44 portion and you dump the last 12 bits probably (I don't know the exact number) because it's too soft to carry much information so you have the top high level 12/44 which is what a regular CD player would end up playing and then you encode the remaining 44kHz-352kHz 24-bit information (which are probably so low signal that it'll already be contained in the bottom 8 bits) into the remaining low level 4 bits within the 44kHz and you add them up and get 16/44. What I do wonder is if you play an MQA 16/44 file on the Chord instead of a proper 16/44 CD file on the Chord DAVE, would the low-level signal that is part of the encode actually make the recording sound worse? I suspect probably because the whole point of having the DAVE or other Chord DACs is to resolve these low level signals. If Meridian is just going to replace the low level signals with encoded high frequency signals, I'm not sure if it'll actually improve the sound.

 

[DaveRedRef-III]

Thanks for the feedback romaz. This points to MQA being primarily a simple recording/mastering file solution rather than requiring anything special in the conversion. Obviously a better mastering (with better timing) will sound better in the same way that any superior Red Book mastering will. However, MQA was born out of recognition for the timing inadequacies of digital conversion. MQA corrects blurring/timing errors in the studio AD conversion as I understand it and so it would be logical to assume the same problem is potentially there on the DAC end too. I can't help thinking that Meridian will already understand how best to covert such a file back into analogue, avoiding the same timing errors which have plagued digital conversion for 30 years. I suspect there will be a significant quality differential between differing Dacs handling MQA files in the same way Red Book sounds different through every DAC. MQA conversions will not be equal and Dac makers who actually address the protocol specifically will likely deliver something closer to the full potential of MQA (as envisaged, designed and currently demo'd by Meridian) imo. Hopefully Dave will do it justice. Given Robs design I think it has a better than average chance of being one of the better DACs for this new protocol.

 

[Mython]

Raise your hand, anyone who thinks this is, by far, one of the most interesting threads, ever, on Head-fi?
 

 

[romaz]

 
As far as I understand it, MQA is an umbrella label for two separate technologies which can operate independently or combined.
 
(I) One feature is that hi-res files can be encoded ("folded" in Meridian's terms) and packaged into 44.1 or 48 kHz files. Without MQA decoding they will play "as -is", and Meridian said that there may be some improvement even then because they apply an appodizing filter.  If MQA decoding is available, the player will un-pack the file and play it in hi-res, up to either the source rate of the material or the max rate that the particular device will support. (See the following for a detailed explanation: http://www.theabsolutesound.com/articles/beyond-high-resolution/)
 
(II) The second aspect of MQA goes one step further.  Meridian has been working with studios to go back and calibrate the recording chain used on certain session of interest, in order to build a signature of how the master recordings were made.  This permits the replay DAC to "correct" for the recording process, and hence play-back something much closer to the original music being recorded.  I *think* that this requires a hardware decoder, but have no more info than that.  No idea how the marketing or labelling will work, but we'll doubtless see more as materials and players roll out. (See this overview from 2L: http://www.2l.no/pages/album/120.html)
 
(I) being generic should be relatively easy to implement, and so anything that offers Tidal streaming, for example, would be the most obvious first candidates.  (II) though requires that the replay DAC, which is unique to each player, applies the necessary corrections in order to account for what was learned about distortions or specific characteristics of the recording chain.

Yes, this is my understanding as well.  When I asked if an MQA file that contained a 24/192 track within would sound equivalent to a non-MQA file with an equivalent 24/192 bit-depth and sampling rate, I was told the MQA file should potentially sound better based on how they have been able to extract more information from certain recordings as you have described above.  However, as it was discussed with me, this "correction of the recording process" takes place at the decoder and not the DAC per se.  In other words, if the decoder is at the level of the external streamer, then the capabilities of the DAC doesn't matter as long as it is capable of playing the file's bit-depth and sampling rate.  

 

[bmichels]

  MQA....With the DAVE, there should be no issues that I foresee as the DAVE, through USB, is capable of playing everything up to 4x DSD and 768 KHz sampling.

 
This is very good news.  So we can go ahead and buy DAVE without any "future proof" issue ?  correct ?
 
Alternatively, the Aurender A10 with Streamer + DAC, booth MQA compatible, is a safe solution, but... is the DAC inside the A10 at a satisfactory high end level ? 

 

[highfell]

This is very good news.  So we can go ahead and buy DAVE without any "future proof" issue ?  correct ?

Alternatively, the Aurender A10 with Streamer + DAC, booth MQA compatible, is a safe solution, but... is the DAC inside the A10 at a satisfactory high end level ? 

are you really prepared to buy another format of music , Ie one which has been "MQA'd" that you already have on Vinyl, CD, SACD, DSD, Hi Res etc. ?

 

[romaz]

  I have to say I find the MQA remastering of old recordings, particularly old digital recordings a little suspect.

 
Someone with more knowledge about MQA will need to step up and correct me but my understanding is that no upsampling takes place with MQA.  I have yet to buy into the benefits of upsampling personally and so if this is what's happening, I would agree with you. 
 
I will say, however, that in the demo that I had the opportunity to take part in, a Mytek Brooklyn DAC was used that had a built-in MQA decoder that was defeatable, meaning I could toggle it on and off.  An MQA file was streamed in real time from Sweden via a simple Windows laptop running a beta version of Tidal with MQA capability and streaming occurred very smoothly.  I was told the file that was streamed was actually recorded in 24/352 using a recorder with that ability (no upsampling) and with this DAC connected to an LCD-X, the sound was impressively good with the decoder turned on and much less dimensional with the decoder turned off.  The effect was similar to what you would hear with the DAVE against other DACs although the effect was less pronounced.
 
Is this something I would wish to have?  With other DACs, I think most would say absolutely, yes.  But with the DAVE, it seems that the DAVE can already accomplish this and more with standard 16/44 files and so you could make the argument that MQA is unnecessary.  The question I have is will MQA + DAVE lead to something altogether more extraordinary?  If so, then sign me up because I see no downside to the consumer here.

 

[bmichels]

are you really prepared to buy another format of music , Ie one which has been "MQA'd" that you already have on Vinyl, CD, SACD, DSD, Hi Res etc. ?

 
You are right, no one will want to purchase MQA versions of the thousands High-Res audio files that he get on his HD.
 
For me MQA is of interest ONLY for streaming High-RES from TIDAL or other MQA streaming services.

 

[highfell]

You are right, no one will want to purchase MQA versions of the thousands High-Res audio files that he get on his HD.

For me MQA is of interest ONLY for streaming High-RES from TIDAL or other MQA streaming services.

OK that would work with me as well.

Stupid question ? - if you take the digital out of your iPhone playing a Tidal MQA streamed piece of music into any old DAC versus digital out of your iPhone for a non MQA Tidal streamed piece of music into the same DAC , would the former sound any better ?

 

[Sonic77]

Dave is in the house! Haven't set it up yet, although I listened to it at the hi-end audio store through $30k Magico speakers. Sounded fantastic!!

 

[bmichels]

Originally Posted by romaz /img/forum/go_quote.gif
 
 
I will say, however, that in the demo that I had the opportunity to take part in, a Mytek Manhattan DAC was used that had a built-in MQA decoder that was defeatable...

 
 
was it really the Manhattan ? Not the new Brooklyn ?

 

[Mython]

  $30k Magico speakers.

 
 
Yummy...

 

[romaz]

   
 
was it really the Manhattan ? Not the new Brooklyn ?

Yes, you're right, it was the Brooklyn.

 

[Beolab]

Someone with more knowledge about MQA will need to step up and correct me but my understanding is that no upsampling takes place with MQA.  I have yet to buy into the benefits of upsampling personally and so if this is what's happening, I would agree with you. 

I will say, however, that in the demo that I had the opportunity to take part in, a Mytek Brooklyn DAC was used that had a built-in MQA decoder that was defeatable, meaning I could toggle it on and off.  An MQA file was streamed in real time from Sweden via a simple Windows laptop running a beta version of Tidal with MQA capability and streaming occurred very smoothly.  I was told the file that was streamed was actually recorded in 24/352 using a recorder with that ability (no upsampling) and with this DAC connected to an LCD-X, the sound was impressively good with the decoder turned on and much less dimensional with the decoder turned off.  The effect was similar to what you would hear with the DAVE against other DACs although the effect was less pronounced.

Is this something I would wish to have?  With other DACs, I think most would say absolutely, yes.  But with the DAVE, it seems that the DAVE can already accomplish this and more with standard 16/44 files and so you could make the argument that MQA is unnecessary.  The question I have is will MQA + DAVE lead to something altogether more extraordinary?  If so, then sign me up because I see no downside to the consumer here.

It is like music to my ears when you describe the difference btw MQA and standard format recorded in 16/44.1 gives less diffrence to what DAVE does to an ordinary 16/44.1 file
against other DACś on the market
So if everyone had a DAVE there would not have bin any room for the MQA format almost

(When you toggel the switch to off , in what format / resolution was it then played in? )

 

[brightonjel]

  Yes, this is my understanding as well.  When I asked if an MQA file that contained a 24/192 track within would sound equivalent to a non-MQA file with an equivalent 24/192 bit-depth and sampling rate, I was told the MQA file should potentially sound better based on how they have been able to extract more information from certain recordings as you have described above.  However, as it was discussed with me, this "correction of the recording process" takes place at the decoder and not the DAC per se.  In other words, if the decoder is at the level of the external streamer, then the capabilities of the DAC doesn't matter as long as it is capable of playing the file's bit-depth and sampling rate.  

Hmm, interesting.  From what I took away (from a Meridian-led session in Silicon Valley as part of rolling-out MQA) then in order to fully benefit from the "re-mastered" source, the replay chain needed to know not only the characteristics of the recording chain, but also of the decoding electronics (i.e. the DAC).  The idea is to get a close as possible to the original analogue waveform and MQA therefore needs to remove both recording non-linearities and decoding non-linearities.  That requires knowledge of both the recording chain and that on the decoding end, as both will have their own conversion signatures.  Anyway, doubtless more will become clear over the coming months, marketing notwithstanding!