HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

Are CD's the future?

Imagine that you could compress a hi-res audio file into a data format that could be read and played as a standard CD but then 'unfolded' by a DAC to present a DSD-style level of playback.

Cool ! Well, that is what an MQA-encoded CD does. It conceals an extra level within the 16-bit signal that allows a custom decoder to create an analogue waveform of much higher definition than a CD would be capable of.

Seeing as I have one MQA DAC in the arsenal here, curiosity led me to Amazon, which does have a selection of MQA-CD titles but they are mainly expensive Japanese imports. One disc that was affordable enough for this experiment was the 30th anniversary reissue of Jazz-Rock supergroup Fourplay's debut album. Right, let's try that.



The album arrives with customary alacrity and I load the disc into the Kiss DVD player, expecting the Sabaj A20d DAC to automatically detect MQA encoding. It doesn't. Hmmmmm.

Yes the CD is playing, there is music but it ain't MQA. Scrolling through the DAC's menu I spot an SPDIF setting that allows for an extra processor to be activated. Turning this on gets the MQA logo appearing in the display. Yay! Let's listen.

Fourplay are a First Division lineup of Jazz musicians making music in a similar vein to Stanley Clarke or the Yellowjackets. Laid-back, impeccably played and recorded. A fine choice for checking out the SQ of this format.

The soundfield is huge, organic, the instruments placed with oodles of space around them. Nathan East's bass is rich, fruitily solid. An analogue experience that is markedly different to what I am used to from CD playback.

Turning the SPDIF processor off allows me to hear the CD as it would come across on a non-MQA-eqipped setup. The sound is dull, muffled. Top- end is recessed with the sparkling space and detail sucked away.

This reminds me of HDCD discs that can sound awesome when played on a system that can decode them properly but are otherwise unimpressive. The MQA data takes up some of of the CD's 16bit signal, leaving 13 bits for 'normal' CD playback. A significant reduction in quality.

Great if you have an MQA-capable system, worthless if you don't.

Next experiment is to rip this disc to the NAS and see what happens.

More later. Stay tuned ...

13 bit pcm is what the bbc used for fm radio broadcasting in the seventies, gives a frequency range of up to about 15k so its no wonder it sounds as it does.

https://www.bbceng.info/Technical%20Rev ... ts-fm.html

Interesting stuff! That DAC of yours continues to impress. An MQA module is available from Metrum; I've often wondered about adding one to my Adagio.

Confused ? You will be ....

Ripping the Fourplay CD to an uncompressed WAV file using EAC (bit-perfect - in theory). Then it's off to try this out on various in-house streamers.

On the non-MQA installations I'm getting that slightly muddy, unfocussed sound that is passable but far from spectacular. Then back upstairs to the Sabaj A20d this time fed via USB from a Volumio PC. Firing this up, I don't get the MQA logo - why not? USB ought to pick it up straightaway. A moment pondering and then I go into Volumio and switch off the internal resampling function. Another attempt and yes - the MQA sign flashes up and we have the same highly impressive SQ that was coming off the CD.



But - I have a plan so cunning you can pin a tail to it and call it Marmaduke ! A trick I learnt with HDCD's is to convert them using DBPowerAmp, changing the 16bit format to 24bit. With an HDCD this unlocks the additional dynamic information and allows the HDCD to unfold to the 20bit signal that is encoded on the disc. This is why I have accumulated a large selection of HDCD's despite the fact that my relatively-recently acquired Kiss DVD player is the only one I have with onboard HDCD decoding.

Creating a new 24bit WAV file with DBPowerAmp Audio Converter, I then do the same round of setups, and can now compare the 16 and 24-bit versions. The non-MQA DACs all sound far better with the 24bit file, the 'bite' and top-end sparkle is there along with a more spacious, airy feeling. Nice! Don't know if the MQA data has actually been incorporated but this is a finer listening experience.

Back upstairs and the Sabaj / Volumio installation - where things turn out to be precisely the opposite !!!!!! Where the 16bit playback had that MQA magic, the 24bit file now sounds oddly dull. Weird. The MQA logo is still on but I'm not getting the same quality.

So, MQA signals don't like being messed around with, no conversion, no resampling, no nothing and then the DAC can take that encoded data and turn it into high-res music output. For non-MQA-capable DAC's, the expansion to 24bits does help but I haven't a clue why.

Is it worth it? I know that a lot of either Tidal or Qobuz hi-res streams are MQA, so that might sound impressive - if you have a DAC that can handle it. Not being into streaming myself - I can't give an answer there. What I might do is invest in a Jap copy of an album that I do know well and see how the SQ works on that - back to Amazon, I suppose.

Learning curve again.

What would be good to compare is that Album but on a straight CD release . I have a feeling that what happened with SACD might well be going on here . In the early days of SACD they very carefully remastered the Albums and used the same master for both the SACD and the CD level on the dual play discs . When listened to the CD layer sounded very close and nearly as good as the SACD level . After this Sony used two different masters for the CD and SACD cuts making sure the CD master was not as good as the SACD one . After this there was many reviews saying how much better the SACD sounded and so boosted sales for both players and Discs . As MQA have gone in to administration I suspect there will be not many more discs issued with MQA and Tidal are very quietly replacing their catalogue with straight HiRes versions and keeping very quiet about MQA . I suspect the CD master has been doctored to sound as it does to make the MQA unfold and playback sound much better but doubt we will ever get proof about this . Sony got caught out and exposed by a whistle blower or we would never have know what was going there either .

Bencat57 wrote: ↑Wed Jul 26, 2023 11:48 am What would be good to compare is that Album but on a straight CD release . I have a feeling that what happened with SACD might well be going on here . In the early days of SACD they very carefully remastered the Albums and used the same master for both the SACD and the CD level on the dual play discs .

That is my next step - Amazon have MQA-CDs from the likes of The Police and Yes that I also have on remastered standard CD's, might get one of those to compare.

The SACD's I have are almost all from my neighbour's Channel Classics label. Although I don't have an SACD player these all sound exquisite as normal CD's.

All things being equal I find 24 Bit superior to 16 Bit, but the quality of mastering is far more important. I have avoided MQA, too much smoke and mirrors and now I don't think it has much of a future.

CN211276 wrote: ↑Wed Jul 26, 2023 1:08 pm All things being equal I find 24 Bit superior to 16 Bit, but the quality of mastering is far more important. I have avoided MQA, too much smoke and mirrors and now I don't think it has much of a future.

100%. Mastering is everything.

Had a listening session last night comparing the Fourplay MQA disc against standard CD releases from other outfits in the same genre and style, primarily Yellowjackets, Pat Metheny Group and Stanley Clarke.

I must confess a light disapointment as the MQA-encoded playback wasn't really any better than the Yellowjackets first album, certainly not sufficiently to justify the hassle and expense that MQA involves.

Doing a test with the 16bit file with MQA active against 24bit, no MQA but upsampling to 384 KHz, was also a touch-and-go scenario. MQA has a slight edge in space and definition, but it wa a case of splitting hairs.

Don't think I will go any further down this particular rabbit-hole due (mainly) to the expense and hassle, but also (as has been said) the MQA company has folded and this format seems destined for the Great Dustbin of Failures in the Sky (along with Betamax, DCC, V2000, Laserdisc etc.).





Although, the music of Fourplay is rather good - if you like laid-back, soulful Jazz-Rock exquisitely played by a lineup of Master musicians.

Oh yes, afterthought ....

One thing I will say in favour of MQA is that the format does seem to be very resilient to jitter-induced problems. Seeing as the DAC does most of the work in unfolding and expanding the analogue signal from the 16-bit datastream, any slight timing problems appear to be eradicated by the MQA processing.

This is a big plus-factor as the struggle to reduce jitter is one of the major hurdles for digital-based audio.