Why is everyone so down on MQA?

Mqa

official answer from senior tech advisor of Mcintosh

yes Mcintosh

we do not use or recommend MQA as it sounds muddy ‘

i have it on my email from 2 years ago and they still don’t recommend it nor will they ever!

@dalims4

From the very same Web page:

"... our encoders remove the audible ‘digital blur’ that builds up in studio production."

"But a lossless file is just a digital container ..."

So, they modify the digital master first, and then losslessly pack the changed data.

The papers explaining how MQA works claim that there is no perceptual loss. However, technically there is data loss, because original signal gets compressed: they call it "folding", yet it doesn't change general nature of the process.

Moreover, it appears that a signal's digital representation can only be perceptually transparently folded into MQA format if it fits into prescribed triangle on energy vs frequency graph. The energy of higher frequency components has to be below descending line defined in MQA specification.

Correspondingly, experiments with publishing music on Tidal in MQA format uncovered two types of losses: additional noise slightly beyond what mere dithering would add, and rather significant artifacts triggered by signals not fitting into the MQA triangle.

So, like any competently designed compressed format, MQA strives to be perceptually transparent on signals falling within its domain of applicability. Which, arguably, are the most music signals. And in this sense, it appears that there shall be no meaningful losses for most signals.

However, MQA can't be technically called a lossless PCM compression format, because a lossless format has to encode and then decode any PCM file with a supported bit depth and sampling rate in a bit-perfect manner. FLAC is an example of such format. Yet its compression factor isn't high - typically around 2x.

Correspondingly yet again, subjective evaluations of MQA-encoded recordings are mixed. Most files do indeed appear to be encoded in a perceptually transparent manner while being significantly smaller than FLAC. Others reportedly do not. If MQA was consistently the home run it claims to be, we wouldn't be having this conversation.

It fascinates me that people who eschew simple tone controls go for tech that unnecessarily complicates encoding and decoding digital data. Simpler should be better. Things like DSP or EQ (yes, even vinyl RIAA) solve specific issues. With the cost of bandwidth and storage getting cheaper all the time, additional compression (and lossy compression to boot) isn’t needed. Adding in all the proprietary and licensing nonsense or the DRM discussion and it’s just not worth the bother to me. There would have to be a unanimous outcry proclaiming better SQ rather than the muddled mixed bag we have now for me to even try it. 

One nice feature Tidal recently added was the option to view the scrolling lyrics as the song plays. This is nice for my girlfriend/daughters/friends who want to sing along on the PA system.

When listening to a random playlist, it’s easy to hear when a "non-master" song gets thrown in the mix, it’s very flat.

Also not a fan of all the hip-hop I have to filter through since Jay-Z bought it.

I wish I understood MQA better.  The way I understand it is it was designed to fold the files 7 times in order to pass the data through slower internet speeds.  Now with internet speeds being 1 gig this is no longer necessary.  I have a BlueSound Node 2i.  The guy from The Cable Company convinced me to hook up my BlueSound to my ARCAM via an expensive digital cable.  I told him this would reduce MQA from 7 unfolds to 1 and reduce sound quality.  He told me by using a digital cable, I would be able to use the DAC inside my ARCAM which was better than the BlueSound.  Maybe QObuz sounds better because you don't have to fold files and because of faster internet speeds this helps QObuz to sound better.  The rep from ARCAM cane to my house and conducted a blind test and I picked QObuz every time.  I am a afraid to change because I do like the layout of Tidal and don't know how QObuz would look in comparison.  It would help if QObuz showed how their graphics look in comparison.  I feel kind of stupid about this.  This group is far more knowledgeable.