MQA disappointing


(crenca) #1571

Ideally, however the upsampling of 99.9% of the DAC’s on the market is pretty good. So good in fact, whatever is left to be gained in most cases is for the “audiophile” - guys like you and me who have HQPlayer, expensive dacs and playback chains, etc. If for the 99%, 320kbs MP3 is indistinguishable from 16/44, then what is the percentage who can benefit from hi res? 1%? I think that is too high. .01%? Probably something like that. Which brings us back to the market - how can hi res ever catch on, or 16/44 continue hanging on, if so few are in any way interested in the ideal?

My point in saying all this is to simply point out that hi res, even 16/44 as a mass market sell is tough - so few can even begin to take advantage of the quality.

Into this market reality walks MQA, trying to sell itself as sound quality product. Even if this were true (of course it is not) it would be a bit of a fool’s errand it seems to me…unless of course the sound quality speak is just a marketing angle.

That said, it is interesting to see the inconsistencies. On the one hand, the loss of information is “inaudible”. On the other, MQA is ostensibly a “hi res” product and hi res is a benefit…for some reason. As usual, MQA wants to have it both ways. Also of course, those who end up defending it both ways never seem to have a grasp of the background - why hi res in the first place, the understanding of the contradiction, etc.


#1572

Like the guy said, who are you to say whether it matters or not? Stop deflecting.


(Rudi) #1573

There is a debate whether the difference between 16/44.1 and 24/96 is audible.
This article goes right to the heart of this thread. It cites two studies:

The well known Meyer / Moran saying that the difference cannot be heard.

And a treatise by Bob Stuart which says, the CD cannot reproduce everything that is audible.

Then there is the view by Dan Lavry that the optimal sample rate for audio reproduction is around 60kHz.

Take your pick.

I tend not to worry too much. The variability of different masterings is so much greater that the maybe audible difference between formats, that I will chose the better mastering over the format.

The Shelby Lynne CD I mentioned further up blows away the SACD.
I find the Jackson Browne MQA Masters on Tidal (slightly) better than the hires on Qobuz.

Now that’s about listening preferences.

Whether MQA produces (measurable) distortions is a completely different (technical / objective) discussion. I think that one has been answered.

Whether some folks actually prefer those distortions (as some people prefer the crosstalk and distortions of vinyl to digital) is yet again another (subjective) question.

It would be nice if we could keep the different questions apart and not answer a question with the answer to a different question, which is what is constantly happening in this thread

  • “MQA sounds terrific”
  • “But MQA is lossy and produces distortions”

#1574

I really don’t understand the point you are trying to make.

My opinion is as valid as that of anyone else - no more than that. From what do you think I am deflecting?


(Jeremy) #1575

Good question. In theory NO.

In practice, I think many DACs suffer from differential non-linearity and aliasing issues and often upsampling can ameliorate things by randomizing non-differential effects and eliminating aliasing artifacts. In theory it should not be necessary but poor quality, poor design and build of DACs means YMMV. I have a DAC that doesn’t care if you upsample or not - it always sounds identical provided the source file is the same. That might be because it fundamentally uses upsampling as the basis for conversion.


#1576

In fact 16/44.1kHz CD can reproduce all the audible information up to 20kHz which is sufficient enough (Though some high order harmonics may be missing). The issue is the cut off frequency is around 22.05kHz and any over-sampling filter (typical 8x) need to attenuate this down by at least -90dB or more to prevent aliasing. This close proximity to the audio range, meant filter has to equipped with a sharp cut-off characteristics. This introduces ‘ringing’ in both pre and post typical standard filter design.

MQA partially solves this by using MQA filter (a variant of minimum phase filter) it’s cut off frequency is now at 44.1/48kHz instead of 22.05/24kHz bandwidth of a typical standard filter. This explains the fact MQA core will always output 88.2/96kHz regardless whether the original sample is 44.1/48kHz or higher. MQA may partially solve this ringing issue but because the filter cut off is 2x higher than typical standard filter, there’s a very high chance of aliasing (leaky). MQA filter belong to a group of non-linear filter; meaning distortion will increase exponentially to higher frequencies. Combined with this distortion and aliasing, I wonder this abnormalities will influence the typical sound ‘signature’ of MQA.

The way to fully solve all these issue is to sample higher, in fact the sweet spot is 176.4/192kHz, this is 4x away from the audio range and any filters designed to attenuate at 176.4/192kHz is a slow roll-off; such filter introduces virtually little to no ‘ringings’. Best of all, you don’t need any oversampling though most DAC will oversample to 352.8/384kHz.


#1577

I don’t find ‘MQA sounds terrific’ it just another typical sound signature that may suit certain type of listeners; probably they fall into those who appreciate a more ‘analog sounding’.

MQA is lossy in data form but when conveying musical details, it is close to be subjectively transparent. The distortion you are taking about is all about the MQA filters used.


(Jeremy) #1578

This kind of ringing isn’t audible. This is MQA marketing BS. If a DAC sounds different or better because of the upsampling then the upsampling is simply improving DAC performance. Examples would be reduction in IMD distortion, aliasing, poor leaky filters or differential non-linearity.


(Erik Barsingerhorn) #1579

MQA part 2: how does MQA work


(Erik Barsingerhorn) #1580

No more words are needed.


(Jeremy) #1581

The video covers how it works but neglects to mention that MQA methodology is not true high fidelity because it distorts the original signal by time and amplitude smearing.

The claims that MQA fixes audible issues is false.


(Jeff) #1582

Another comedic Hans video, The first one was so completely wrong I won’t waste my metered internet on this one.


(crenca) #1583

Han’s is much like Bob Stuart. They appear to be using the same language as digital audio and software, signal processing, and the like as everyone else. However, scratch the surface and you realize they either don’t know what they are talking about at all, or they are using and abusing the plain meaning of words for their own $ends$…


#1584

Oh dear. here we go again, re-treads anyone?

I wish this was “Just a minute” (Radio4)


(Martin Kelly) #1585

We’re just caught in ‘The Twilight Zone’. Again.
They cancelled that series. Eventually.


(crenca) #1586

For example what, exactly, does Bob S mean by the phrase “natural sound”?

Does Hans use this term as well?


#1587

Ask him, I’m sure he’ll give you the time of day… [Moderated.]


(Jeff) #1588

Bob actually has something to say that is not just regurgitated marketing? That would be new and actually welcomed!


(Chris ) #1589

Lol, you will get plenty of words from the anti MQA faction, that’s Ok… I have heard it all and then heard MQA… I know what I like.


#1590

Think you missed the point, it’s about this “thread” aka Cranki’s propaganda tool of anti-MQA endless loop tape…