MQA is Vaporware

[The Computer Audiophile]

1 minute ago, christopher3393 said:

 

Is that:

a) an objective statement

b) a subjective statement

c) a radically subjective statement

d)  both an objective and a subjective statement

e) neither an objective nor a subjective statement

 

⏰

a

[Ralf11]

3 hours ago, firedog said:

JA was correct about that article about the Pono and hi-res. Basically, he took people who listened to mp3 on earbuds and asked them which sound they preferred. They preferred what they were used to or couldn't hear a difference. 

People can hear what they've trained themselves to hear. Many of these same people SAY they can't tell tell the difference between an mp3 and a CD - until you point out the differences to them a few times - and then they somehow can hear the difference. It's not what's in the source file, it's in how you've trained your brain to interpret what arrives to it - to discern smallish differences or not. 

 

That said, NY shot himself in the foot by exaggerating the difference between the sound of his hi-res files and other files, even mp3. The difference isn't always night and day - in many cases it is pretty small, especially for some types of music recorded at higher mp3 rates. 

 

Yes; see the scientific literature on "Attentional Processes"

[christopher3393]

15 minutes ago, The Computer Audiophile said:

a

 

Ok, so significance is in the eyes, or in this case the ears, of the beholder? So are you saying that significance is subjective and that this is a fact?

[The Computer Audiophile]

Just now, christopher3393 said:

 

Ok, so significance is in the eyes, or in this case the ears, of the beholder? So are you saying that significance is subjective and that this is a fact?

Absolutely.

[lucretius]

18 minutes ago, The Computer Audiophile said:

19 minutes ago, christopher3393 said:

 

Ok, so significance is in the eyes, or in this case the ears, of the beholder? So are you saying that significance is subjective and that this is a fact?

Absolutely.

 

Significance is in the ears of the beholder, only after he/she receives 'special training'.

 

Perhaps @The Computer Audiophile is saying that the underlying 'objective' reality is perceived in different ways?

 

[Tintinabulum]

1 hour ago, Rt66indierock said:

Don't forget the usual fallback you don't have a highly resolving system to hear the difference

My understanding is that you need a fast (high bandwidth) amp to fully benefit from the improvements, why is this so implausible? 

[lucretius]

1 hour ago, Tintinabulum said:

My understanding is that you need a fast (high bandwidth) amp to fully benefit from the improvements, why is this so implausible? 

 

Almost all modern amps have a bandwidth going up to 50 kHz, many go up to 100 kHz, some go to 200 kHz. The bandwidth of hi-res music is one half the sample rate:

 

e.g.

44.1 -> 22.05

48    ->  24

88.2 -> 44.1

96    ->  48

176.4 -> 88.2

192 -> 96

 

Therefore, almost all (modern) amplifiers can fully resolve a 96 kHz sample rate.  Many (modern) amplifiers can fully resolve a 192 kHz sample rate. Add to this that it is questionable whether there is any audible benefit gained from going from a 96 kHz sample rate up to a 192 kz sample rate or higher.  It's almost like you'd have to go out of your way to find an amplifier that cannot resolve hi-res music (vintage equipment?).

 

OTH, speakers are another story.

 

[Rt66indierock]

3 hours ago, Tintinabulum said:

My understanding is that you need a fast (high bandwidth) amp to fully benefit from the improvements, why is this so implausible? 

 

Good grief I have two vintage amps in my office a NAD 3020 that goes to 70k and modified Nikko NA-550 that goes to 50k. And my AR-4x speakers modified by the late Carl Richards that go past 30k according to build sheets. 

 

Can I recommend some new understanding? In any case I'm going order a Kool-Aid  type drink tonight and toast your current understanding and hope you watch MQA Origami about 50 seconds in.

 

 

[Ishmael Slapowitz]

4 hours ago, Tintinabulum said:

My understanding is that you need a fast (high bandwidth) amp to fully benefit from the improvements, why is this so implausible? 

LOL...":high bandwidth" is fabricated marketing dreck parroted by TAS and Stereophile. And lapped up by the gullible...🤣

[Tintinabulum]

5 hours ago, Ishmael Slapowitz said:

LOL...":high bandwidth" is fabricated marketing dreck parroted by TAS and Stereophile. And lapped up by the gullible...🤣

I'm not explaining Slew Rates, Distortion or other relevant factors. You'll have to educate yourself. Basically you hate MQA. Bob Stuart is a sound engineer. Instead of spending all your energy criticising, why not bone up on hifi? Laters...

[firedog]

11 hours ago, lucretius said:

 

How significant can the 'difference' be if special training is required to hear it?

Special training isn't so "special"; pretty much anyone can do it on their own. 

It's special in that you have to care enough to want to hear the difference and spend a bit of time learning the difference. Then you can hear it pretty easily. It also depends a lot on what music you listen to and how it's recorded. Modern pop, rock, hip hop, etc that's heavily volume compressed - there really isn't a significant audible difference. The music/recording itself doesn't have lots of subtleties or dynamic changes, so the differences are  very small - things like a little more realistic sound of cymbals or bass drum. 

With jazz, classical, acoustic musics the difference can be more obvious:  Less volume compression, more "natural" recording techniques, greater dynamic changes within the music, lots more use of the subtleties of instruments and playing. The small details are part of conveying the art. 

It's a philosophical question. The objective difference between 192k or 256k mp3 and CD isn't huge. Neither is the difference between CD and hi res.  How important that difference is to you is subjective. Some people don't care even when they know it's there and can hear it; other's find they get the most enjoyment out of music when they can playback and hear every nuance. 
 

One of the failures of audiophilla is exaggerating the improvements formats make - mostly they aren't night and day - and when you say they are, you invite people to say they can't tell the difference. Another is saying you need really expensive equipment to hear the difference - you don't. You just need pretty good equipment and  to  know what the differences are. Pretty much any decent modern system can produce the differences, at least to an audible extent. 
 

My hearing doesn't go much above 13k anymore at normal volume levels. But I can hear lots of differences younger people "can't".  It's because I know better than they do how to listen. If you point out to them the differences in cymbal or bass drum sounds  between mp3 and CD or high res, they can hear it. It's just they never noticed it before and said "there's no difference". They heard it physically, but their brain didn't present the difference to them as something "heard". There's a difference between hearing sound and perceiving sound. The first takes place in the ears, the second in the brain. 

There is a similar phenom when looking at a painting. Someone who is a casual observer "sees" the same painting as someone with a trained eye. But the person with the trained eye notices  brushstroke, painting technique, small changes in detail such as portrayal of light. The "regular Joe" doesn't.  Can they both appreciate the painting? Yes. But the more sophisticated viewer, who's "learned" to notice detail, has  a more in depth and full understanding of the piece. Probably a greater enjoyment also. 

[The Computer Audiophile]

13 hours ago, Tintinabulum said:

My understanding is that you need a fast (high bandwidth) amp to fully benefit from the improvements, why is this so implausible? 

Are you really saying this is needed to hear the “benefits” of MQA?

[Shadders]

4 hours ago, Tintinabulum said:

I'm not explaining Slew Rates, Distortion or other relevant factors. You'll have to educate yourself. Basically you hate MQA. Bob Stuart is a sound engineer. Instead of spending all your energy criticising, why not bone up on hifi? Laters...

Hi,

When you examine class D specifications, they restrict the measurement bandwidth to 22kHz for THD, as the noise above this is excessive, and would present THD figures woefully worse than class A/B.

 

I do not see any reviewer dismissing class D for its higher frequency (22kHz+) noise when compared to class A/B amplifiers. In fact, there is never a complaint from anyone regarding this - reviewers and the consumer.

 

What this tells you is, that the reality is that high resolution files are not required, no one can hear the difference of the extra content, and any difference is due to mastering etc.

 

MQA is irrelevant, since no one can hear the differences or extra content. The fact that class D amplifiers are so bad in the 20kHz+ region proves this - no one can hear it, they only believe that the can.

 

Regards,

Shadders.

[tmtomh]

7 hours ago, Tintinabulum said:

I'm not explaining Slew Rates, Distortion or other relevant factors. You'll have to educate yourself. Basically you hate MQA. Bob Stuart is a sound engineer. Instead of spending all your energy criticising, why not bone up on hifi? Laters...

 

I know it's impossible to read through this entire thread before posting, but even a cursory glance at pretty much any page of this thread will reveal that this bogus Appeal to Authority argument - "Bob Stuart is a sound engineer" - has been made and effectively rebutted over and over again. 

 

I agree with you that Stuart should not be dismissed based on a simplistic "he's lying to make money" argument. But your "he knows what he's talking about so it must be valid" argument is just an equally simplistic mirror image of that other argument, and equally without merit.

 

As for distortion, slew rate, and other measures of amplifier performance, I think you'll find that a lot of members here know exactly what those mean and have more than a surface level of knowledge. So when people ask you what those measures have to do with an amplifier's ability to properly amplify an analogue input that originated as high-res digital content farther back in the equipment chain, it's not because they don't understand amp specs. It's because you have provided no explanation of the connection between those amp specs and the ultrasonic content of high-res sources.

[John Dyson]

7 hours ago, Shadders said:

Hi,

When you examine class D specifications, they restrict the measurement bandwidth to 22kHz for THD, as the noise above this is excessive, and would present THD figures woefully worse than class A/B.

 

I do not see any reviewer dismissing class D for its higher frequency (22kHz+) noise when compared to class A/B amplifiers. In fact, there is never a complaint from anyone regarding this - reviewers and the consumer.

 

What this tells you is, that the reality is that high resolution files are not required, no one can hear the difference of the extra content, and any difference is due to mastering etc.

 

MQA is irrelevant, since no one can hear the differences or extra content. The fact that class D amplifiers are so bad in the 20kHz+ region proves this - no one can hear it, they only believe that the can.

 

Regards,

Shadders.

Agreeing, and furthering you statement about higher frequencies.  Actually, excess HF is troublesome in certain kinds of analog HW -- and can certainly be problems in the digital realm (aliasing for example.)

 

If one  looks at op-amp specs (even really good ones), the distortion tends to increase fairly rapidly above a  nominal frequency in the range of 5kHz through maybe 20k or more at times (I have some very interesting and detailed references in that regard -- if interested.)

Also, the shape of the distortion curves depend on signal level and amplifier (even op-amp) loading.  Such curves are *very* interesting, esp on so-called 'premium' type op-amps.  Some are actually pretty good (some in the TI series.) 

 

Negative feedback (of course) doesn't solve all problems, and lack of negative feedback doesn't solve all problems also.  It is a matter of competent design, and it is simply not competent to supply excessive unusable HF material to any piece of HW.   It is generally best to remove analog signals above a reasonable maximum -- say think about starting to roll off at 22kHz, do something at least at 30kHz, and it is nice to be down quite a bit by 50kHz.

 

Actual, real pro equipment typically forces a rolloff somewhere above 20kHz (DolbyA, for example is pretty much extinguished at 40kHz)  simply for EMI and other such issues.  Oh so often, when I look at 'high res' material with sample rates above 48kHz, most of the so-called audio is digital interference and noise reduction splats.

 

I sure hope that people who see 'interesting' stuff above 20kHz are very often either seeing audio that they cannot hear, or even  more often seeing various forms of distortion or various kinds of coherent (e.g. digital or RF generated) noise.

 

Now, if there is 120dB (equivalent) audio at 22kHz, there might be some people who can 'hear'  the sound -- most likely the ACTUAL audible effects will be artifacts from distortion.

 

In fact, most of the 'improvement' by dealing with significant signal above 20kHz is an *increase* in distortion -- which sometimes creates a mirage of detail.

 

John

[lucretius]

14 hours ago, firedog said:

It's a philosophical question. The objective difference between 192k or 256k mp3 and CD isn't huge. Neither is the difference between CD and hi res.  How important that difference is to you is subjective. Some people don't care even when they know it's there and can hear it; other's find they get the most enjoyment out of music when they can playback and hear every nuance. 

 

Bravo! Your case is well stated. Nonetheless, I have to disagree. I agree with John Dyson's post on the subject.

 

But I am curious about one thing.  In your signature line, you mention the Kii Three speakers in both your main and secondary system (very nice speakers BTW -- I am wiping up the drool). IIRC, the frequency range specified for Kii Three speakers is 30Hz to 25kHz.  Therefore, any sample rate over 48kHZ appears to be wasted, since the top end of the speakers is 25kHz. So why the Kii Threes if you believe that  there is some difference between 48kHz and 96 or 192kHz sample rates?

[Shadders]

2 hours ago, John Dyson said:

Agreeing, and furthering you statement about higher frequencies.  Actually, excess HF is troublesome in certain kinds of analog HW -- and can certainly be problems in the digital realm (aliasing for example.)

 

If one  looks at op-amp specs (even really good ones), the distortion tends to increase fairly rapidly above a  nominal frequency in the range of 5kHz through maybe 20k or more at times (I have some very interesting and detailed references in that regard -- if interested.)

Also, the shape of the distortion curves depend on signal level and amplifier (even op-amp) loading.  Such curves are *very* interesting, esp on so-called 'premium' type op-amps.  Some are actually pretty good (some in the TI series.) 

 

Negative feedback (of course) doesn't solve all problems, and lack of negative feedback doesn't solve all problems also.  It is a matter of competent design, and it is simply not competent to supply excessive unusable HF material to any piece of HW.   It is generally best to remove analog signals above a reasonable maximum -- say think about starting to roll off at 22kHz, do something at least at 30kHz, and it is nice to be down quite a bit by 50kHz.

 

Actual, real pro equipment typically forces a rolloff somewhere above 20kHz (DolbyA, for example is pretty much extinguished at 40kHz)  simply for EMI and other such issues.  Oh so often, when I look at 'high res' material with sample rates above 48kHz, most of the so-called audio is digital interference and noise reduction splats.

 

I sure hope that people who see 'interesting' stuff above 20kHz are very often either seeing audio that they cannot hear, or even  more often seeing various forms of distortion or various kinds of coherent (e.g. digital or RF generated) noise.

 

Now, if there is 120dB (equivalent) audio at 22kHz, there might be some people who can 'hear'  the sound -- most likely the ACTUAL audible effects will be artifacts from distortion.

 

In fact, most of the 'improvement' by dealing with significant signal above 20kHz is an *increase* in distortion -- which sometimes creates a mirage of detail.

 

John

Hi,

There are some excellent opamps available from TI - specifically the LM4562, which has a THD of <0.00007% at 20kHz. Are the detailed references from TI ?. Thanks.

 

Regards,

Shadders.

[lucretius]

16 hours ago, Tintinabulum said:

why not bone up on hifi?

 

Talk about "boning up on hifi" --- In the early eighties, I acquired a cheap CD player, then I got rid of my turntable and LP's.  Then almost 20 years later, "audiophiles" and the audiophile press convinced me that I was missing out on something by not having a turntable.  So I acquired another turntable (and some LPs).  This turned out to be a mistake. In no way is a turntable/LPs better than  a CD player/CDs.  Then, sometime in the mid-2000's, "audiophiles" and the  audiophile press convinced me of the benefits of DVD-A and SACD.  So I acquired a universal disc player and starting acquiring SACD's (and 1 DVD-A).  Again, this turned out to be a mistake.  DVD-A and SACDs were not really any better than CDs (mastering is everything).  Then maybe about 5 years ago, "audiophiles" and the audiophile press convinced me of the benefits of hi-res music files.  So I acquired a DAC that could play these hi-res files. Yet again, this turned out to be a mistake.  Music files with a greater than 48kHz sample rate are no better than CDs (again, mastering is everything).  Then along comes MQA -- I don't even want to go there, LOL!  This leads me to my question: If I wanted to "bone up on hifi", then who exactly should I listen to?

[esldude]

Here is a question I'd like ole Bob to answer.  Let us suppose he is right as rain and MQA is wonderful and a benefit.  I don't know if it will succeed, drag on making a little change for Bob before disappearing, or be a total flop.  But let us assume Bob is concerned it just never caught fire.  It is going to disappear. 

 

So Bob, since MQA is going to die on the vine, would you open up all knowledge about how it works, and make it a free and open source process?  Not asking you to do it for free, but give us an estimate of its cost to develop so far.  Get the record companies the big ones, there aren't many, to agree to pay you over 10 years, 2 times the cost of devlopement from MQA encoded revenue.  At which time you'll open source it so it can never, ever become DRM, and so everyone will know how it works.  You'll benefit from your work, and you can rest easy knowing you've made music better for the whole world. Would agree to that Bob?

 

BTW, in a recent paper Stewart talked about MQA being intended as a encode once and decode once process.  That you couldn't encode and decode multiple times.  That it was different than conventional PCM that way since it used B-splines and gentler filtering.  One more point to make you think it is intended to be something of a DRM process. 

 

Free download of the AES paper.  Only available since last month. Stuart and Craven.  Some of it you'll recognize from the past some of it is new at least hearing it from MQA. 

http://www.aes.org/e-lib/browse.cfm?elib=20456

 

Started a new thread on the paper.

 

[Rt66indierock]

1 hour ago, lucretius said:

 

This leads me to my question: If I wanted to "bone up on hifi", then who exactly should I listen to?

 

Me

[sandyk]

1 hour ago, Rt66indierock said:

Me

 Hi Stephen

 I would respectfully suggest that we don't dilute this thread with silly arguments about amplifier bandwidth requirements, human hearing capabilities etc.

 In fact,  it may even be an advantage to roll off MQA encoded music, if we end up being stuck with it , (mainly due to greedy Entrepreneurs )  quite savagely from 22kHz to remove the possibility of their false information and added noise artifacts from being seen by the amplification chain at all. This may be hard to do with current filtering techniques though, without degrading the existing music.

 

 I would also gently remind you , that there are a large percentage of A.S. members who LOVE the high res formats, including 24/96 , 24/192, even 24/384, and especially the most recent DSD recordings with GENUINE music information well above 22kHz.

And even if most of the advantages come down to the more gentle HF  filtering possible with the high res formats, many members still prefer the high res version over the pathetic RBCD standard of 16/44.1.

 To mention as some do, the bandwidth of up to 48kHz , that is in this case a red herring, as 48kHz is normally only used for Audio on Videos, NOT with normal Music ONLY recordings.

 Yes, I do agree that the RBCD standard perhaps should have been 16/48kHz originally, but at the time they even had a lot of trouble getting 16/44.1 right.

 

If you believe that high res is likely to be of no advantage to you, then use the Format Comparison pages available on line to decide if there are likely to be of any benefit to you, however, I would also suggest that you verify this for yourself using a high quality pair of headphones with an extended frequency response to at least 40kHz, not loudspeakers that start to roll off sharply as they approach 20khZ.

 

 Feel free to remove this post after a short time period as it is OFF TOPIC, along with quite a few previous replies.

 

Kind Regards

Alex

[sandyk]

7 hours ago, John Dyson said:

If one  looks at op-amp specs (even really good ones), the distortion tends to increase fairly rapidly above a  nominal frequency in the range of 5kHz through maybe 20k or more at times (I have some very interesting and detailed references in that regard -- if interested.)

 

Hi John

 I wouldn't exactly call the rise in distortion from around 5kHz with the LME49720 (formely LM4562)  a problem.

 (still well under .0001%)

 Incidentally, Mark ,who was on the original design team reported that the HA version (metal can) sounded better that the DIP version despite measuring the same with their Audio Precision gear. I found the same too. (Perhaps improved heat dissipation was the reason?)

 

Kind Regards

Alex

  

LME49720.pdf

[firedog]

8 hours ago, lucretius said:

 

Bravo! Your case is well stated. Nonetheless, I have to disagree. I agree with John Dyson's post on the subject.

 

But I am curious about one thing.  In your signature line, you mention the Kii Three speakers in both your main and secondary system (very nice speakers BTW -- I am wiping up the drool). IIRC, the frequency range specified for Kii Three speakers is 30Hz to 25kHz.  Therefore, any sample rate over 48kHZ appears to be wasted, since the top end of the speakers is 25kHz. So why the Kii Threes if you believe that  there is some difference between 48kHz and 96 or 192kHz sample rates?

One - I can't be 100% sure that differences between hi-res formats are anything other than mastering. 
Two, I don't really understand the question. I don't know of any human that can hear above 20khz - and I don't come close anymore. But I don't understand how that is relevant.
Any good argument for superiority of higher res formats doesn't rest on humans being able to hear extremely high frequencies, or on speakers/systems being able to reproduce them as analog output,  no matter what the system. 

[lucretius]

17 minutes ago, firedog said:

One - I can't be 100% sure that differences between hi-res formats are anything other than mastering. 
Two, I don't really understand the question. I don't know of any human that can hear above 20khz - and I don't come close anymore. But I don't understand how that is relevant.
Any good argument for superiority of higher res formats doesn't rest on humans being able to hear extremely high frequencies, or on speakers/systems being able to reproduce them as analog output,  no matter what the system. 

 

This is from @Teresa and appears to be the main argument for hi-res:

 

"No one (to my knowledge) has ever said we can hear ultrasonic frequencies. The reason to reproduce them is because musical instruments have overtones as high as 102.4 KHz."

 

" … audio energy exists as upper overtones of musical instruments and has an effect on the lower frequencies which we do hear directly. When listening to music we hear the fundamental note and its overtones shape the timbre, this is why an oboe and a clarinet sound different when playing the same note as their overtone series is different. The more overtones available to shape the timbre of the fundamental tone the more accurate the timbre is IMHO."

***********************

 

So the question is: How can this benefit be achieved if some part of the audio playback chain (including speakers) does not reproduce the ultrasonic frequencies?

[firedog]

3 hours ago, lucretius said:

 

This is from @Teresa and appears to be the main argument for hi-res:

 

"No one (to my knowledge) has ever said we can hear ultrasonic frequencies. The reason to reproduce them is because musical instruments have overtones as high as 102.4 KHz."

 

 

 

" … audio energy exists as upper overtones of musical instruments and has an effect on the lower frequencies which we do hear directly. When listening to music we hear the fundamental note and its overtones shape the timbre, this is why an oboe and a clarinet sound different when playing the same note as their overtone series is different. The more overtones available to shape the timbre of the fundamental tone the more accurate the timbre is IMHO."

 

***********************

 

So the question is: How can this benefit be achieved if some part of the audio playback chain (including speakers) does not reproduce the ultrasonic frequencies?
 

This is OT so we should stop the discussion. But that whole idea is unsupported. There are other arguments for hi-res, which have nothing to do with reproduction of ultra high frequencies in the analog output.
Again, I haven't seen any evidence that proper playback of hi res tracks demands speakers and amps with the ability to reproduce those kinds of frequencies. In fact,  filters in the D/A conversion process filter out those high frequencies anyway much of the time.