Thoughts on a Method to Compare MQA and Non-MQA Files

[esldude]

2 hours ago, Lee Scoggins said:

 

I believe there is an AES standard or research that suggests a certain number of seconds is good for aural.memory.  Maybe you could break tracks into short cuts that are played sequentially...?

Jud is hoping to avoid aural memory altogether.  That IS the whole point of what he is trying to do.

 

The extreme difficulty of splitting something into a pair of channels to me illustrates how wrong MQA is.  You don't even have routing control of music.  The crap needs to die.  I wouldn't even care if it is a sonic advance.  It needs to die.  Then someone should give us the sonic advance without all the goofy strings attached.  They won't because the real point of MQA is those strings. 

 

Sorry, I shouldn't turn this into another MQA debate thread. 

[MetalNuts]

10 hours ago, sandyk said:

The record companies and the proponents of MQA have shown that they don't give a shit about accurate technical analyses 

demonstrating it's failings. 

I believe this is a very true statement.  Their most important concern must be $$$.

[Jud]

7 hours ago, Lee Scoggins said:

 

I believe there is an AES standard or research that suggests a certain number of seconds is good for aural.memory.  Maybe you could break tracks into short cuts that are played sequentially...?

 

Already did.  Though informal, a statistical analysis showed people lost detailed information about things like the harmonics that distinguish two acoustic guitars from each other under such a scenario with statistical significance level of p=0.06.  So you create a dilemma: Short enough to remember more accurately, too short to pick up the fine details that people believe distinguish good systems from each other.  There is also academic research that shows in the ABX situation, the "B" sample replaces the "A" sample in the brain's echoic memory store, so you can't even accurately recall what notes were played in the "A" sample, let alone fine details.  See for example http://deutsch.ucsd.edu/psychology/pages.php?i=209 .

 

So go ahead and tell me all about the possibility of a bit of missing soundstage information when using simultaneous playback. I'll take it over the vagaries of (lack of) acoustic memory any day.

[pkane2001]

Just now, Jud said:

 

Already did.  Though informal, a statistical analysis showed people lost detailed information about things like the harmonics that distinguish two acoustic guitars from each other under such a scenario with statistical significance level of p=0.06.  So you create a dilemma: Short enough to remember more accurately, too short to pick up the fine details that people believe distinguish good systems from each other.  There is also academic research that shows in the ABX situation, the "B" sample replaces the "A" sample in the brain's echoic memory store, so you can't even accurately recall what notes were played in the "A" sample, let alone fine details.  See for example http://deutsch.ucsd.edu/psychology/pages.php?i=209 .

 

So go ahead and tell me all about the possibility of a bit of missing soundstage information when using simultaneous playback. I'll take it over the vagaries of (lack of) acoustic memory any day.

 

Gents, I like the idea of doing your own testing and not relying on someone else to tell you that it sounds better. That's one of the reasons I developed DeltaWave. The comparator in DW is one tool where I intend to keep adding functionality and new ideas to improve on audio evaluation techniques. The tool supports the two-channel simultaneous comparison that Jud is proposing here, as well as standard ABX test, and a subjective preference test.

 

What's more the tool allows any of the tests to be run in 'learning' mode where you can see and tell what track is playing, and to then repeat the test in blind mode, where the tracks are randomized. DW also creates a signed report of your blind test, including hashes of the files and all processing DW itself did to match them, so these can be validated by others.

 

You can do a sequenced A/B test, A/B/X test, a simultaneous Stereo X-Y test, or a sequential preference test and get the resulting statistics that demonstrate that your result was not produced by guessing or random choice.

 

DeltaWave is still under development and probably will be for a long time (I like to tinker) but basic functions are there for anyone to try.

 

Regards,

     -Paul

[Jud]

Just now, pkane2001 said:

 

Gents, I like the idea of doing your own testing and not relying on someone else to tell you that it sounds better. That's one of the reasons I developed DeltaWave. The comparator in DW is one tool where I intend to keep adding functionality and new ideas to improve on audio evaluation techniques. The tool supports the two-channel simultaneous comparison that Jud is proposing here, as well as standard ABX test, and a subjective preference test.

 

What's more the tool allows any of the tests to be run in 'learning' mode where you can see and tell what track is playing, and to then repeat the test in blind mode, where the tracks are randomized. DW also creates a signed report of your blind test, including hashes of the files and all processing DW itself did to match them, so these can be validated by others.

 

You can do a sequenced A/B test, A/B/X test, a simultaneous Stereo X-Y test, or a sequential preference test and get the resulting statistics that demonstrate that your result was not produced by guessing or random choice.

 

DeltaWave is still under development and probably will be for a long time (I like to tinker) but basic functions are there for anyone to try.

 

Regards,

     -Paul

 

In other words, the software allows you to use both methods and compare results.   

 

So which do you perform better at, @Lee Scoggins - the test you've suggested or the one I suggest?

[Miska]

3 hours ago, esldude said:

The extreme difficulty of splitting something into a pair of channels to me illustrates how wrong MQA is.

 

It would be interesting to know how well MQA supports multichannel configurations. 2.1, 3.0, 3.1, quad, 5.0, 5.1... Such usually need channel mapping at minimum.

 

[Jud]

1 hour ago, Miska said:

 

It would be interesting to know how well MQA supports multichannel configurations. 2.1, 3.0, 3.1, quad, 5.0, 5.1... Such usually need channel mapping at minimum.

 

 

It doesn't seem to support 2.0 that well yet.  😉

[Jud]

7 hours ago, Paul R said:

 

Both of you guys are probably speaking true, but I admit, I don't know how you can have depth or height with just a mono recording. Would not any such artifacts be only from the speaker or speakers? 

 

I do not listen to very many monoral recordings, and when I do they sound clear and center placed to me, no real soundstage such as with stereo, just more like a phantom center channel. 

 

-Paul 

 

 

Here's a question: How is information about vertical position embedded in differences between left and right channels?

 

By the way, thought of another way to create an impression of height on a mono recording: Reverberation, natural or as an added effect, creates the impression of an overall larger (therefore higher) space.  With that in mind, listen to the famous Coke can "percussion" on "God Only Knows" from Pet Sounds.

[Jud]

37 minutes ago, Jud said:

By the way, thought of another way to create an impression of height on a mono recording: Reverberation, natural or as an added effect, creates the impression of an overall larger (therefore higher) space.  With that in mind, listen to the famous Coke can "percussion" on "God Only Knows" from Pet Sounds.

 

In addition, see the following: https://theproaudiofiles.com/width-height-depth-in-a-mix/

 

This explains why we might tend to perceive vocals, particularly higher range vocals, as located at a greater height than a bass drum or kick drum.

 

Note that neither this nor reverberation requires different information from left and right channels, i.e., mono will serve just as well as stereo to give these sorts of height cues.

[Lee Scoggins]

9 hours ago, Jud said:

 

In other words, the software allows you to use both methods and compare results.   

 

So which do you perform better at, @Lee Scoggins - the test you've suggested or the one I suggest?

 

Best of both worlds maybe?

 

I will say this, I appreciate your creativity at the approach, it seems like two channels would facilitate an understanding of what the deblurring filters do.

[Lee Scoggins]

7 hours ago, Jud said:

 

Here's a question: How is information about vertical position embedded in differences between left and right channels?

 

I think the LEDR test methodology may reveal some information on this topic, Jud.

[Ski Bum]

Here is the method that I use on Roon.  It is admittedly non-scientific, but actually works quite well and has persuaded me as to the reliability of the results.  I've principally used it to compare Tidal MQA files with the corresponding Qobuz hirez files:

 

Using the Queue feature in Roon, queue up at least 6 pairs of corresponding songs, with each pair grouped together but the order (Tidal first or Qobuz first) randomly selected.  By the time I've completed a queue of at least 6 pairs, I can't remember the random selection (I'm 67 years old; you may need to queue more or fewer pairs).  Play enough of the first song of a pair (without opening the file source information) to adequately sample the sound quality, and then move to the corresponding song in the pair and do the same thing.  Then -- AFTER forming an opinion as to which version sounds better -- open the file source information on the second file to determine the  source of the better sounding file.  Then move to the next pair in the queue and repeat.

 

If you truly forget the random selection, this is quite close to a double-blind test.

 

By doing this with dozens of songs, I can now generally pick out a Tidal MQA Studio 24/96 or 24/192 version versus a Qobuz 24/96 or 24/192 version without having to do a comparison.  And, yes, I have formed an opinion as to which version generally sounds better on my system.

 

In case anyone else wants to try this approach, I will refrain from posting my results so that I'm not inadvertently inserting a placebo into another listener's test.

 

 

[sandyk]

7 hours ago, Jud said:

Note that neither this nor reverberation requires different information from left and right channels, i.e., mono will serve just as well as stereo to give these sorts of height cues.

 

Don't forget too, that most speakers have the tweeter(s) and LF driver at different heights on the baffle. 

The listening position should also normally be arranged so that the ears are at a similar height to that of the HF drivers for best results.

[psjug]

9 hours ago, Jud said:

By the way, thought of another way to create an impression of height on a mono recording: 

You could stack your speakers one on top of the other.

[Jud]

1 hour ago, sandyk said:

 

Don't forget too, that most speakers have the tweeter(s) and LF driver at different heights on the baffle.

 

I take it you did not read the linked article, since that's exactly what it says.   

[Jud]

3 hours ago, Lee Scoggins said:

t seems like two channels would facilitate an understanding of what the deblurring filters do.

 

Speaking of admiring creativity:

 

People objected that the dual-mono test would affect soundstage height. Several mechanisms have now been discussed, and not a single one requires two different channels.

 

Now you propose that 2 speakers with differing material are needed to detect filter ringing, and intermodulation and harmonic distortion.  What possible mechanism would you suggest for this?

 

I'm very happy to hear cogent criticism of the proposed method, or have people try it out versus sequential listening and see where they have more success.  But rank speculation just wastes time.  So please provide a reasonable mechanism (you or anyone else), preferably with some support, or let's drop it.

[fas42]

As I've mentioned several times, Audacity has always made it easy to compare tracks in a dynamic situation - simply load both versions, align them fairly accurately, and solo each, switching between them at random, etc. Once you have found a suspicious area, simply select that chunk, and play on repeat a solo'ed track, to build a pattern of sound in your head; then switch to the other version. If there's something significant it will be obvious ...

 

I've used this technique many times over the years; it spotlights the differences ... then it's up to you to decide which version is 'better' ...

[Rt66indierock]

19 minutes ago, Jud said:

 

Speaking of admiring creativity:

 

People objected that the dual-mono test would affect soundstage height. Several mechanisms have now been discussed, and not a single one requires two different channels.

 

Now you propose that 2 speakers with differing material are needed to detect filter ringing, and intermodulation and harmonic distortion.  What possible mechanism would you suggest for this?

 

I'm very happy to hear cogent criticism of the proposed method, or have people try it out versus sequential listening and see where they have more success.  But rank speculation just wastes time.  So please provide a reasonable mechanism (you or anyone else), preferably with some support, or let's drop it.

 

Jud, Lee is here to disrupt any discussion that involves those three letters. Archimago talks about the rational audiophile I wonder if Lee thinks the irrational audiophile needs some representation too?

 

Anyway thanks for this discussion. 

[Ishmael Slapowitz]

 

4 hours ago, Lee Scoggins said:

 

Best of both worlds maybe?

 

I will say this, I appreciate your creativity at the approach, it seems like two channels would facilitate an understanding of what the deblurring filters do.

..Um, or not. You cannot be serious.🙄

 

Do you really believe all schemata you spew? You really can't.