Testing audiophile claims and myths

[bigshot]

Too many "what ifs".

 

[Glmoneydawg]

Possible? I doubt it. Even if it were possible where does it leave MQA files that were originally sourced from analog tape? How will they reverse engineer the by order of magnitude greater flaws around non-linear sonic signatures such as wow, flutter (and scrape flutter), imperfect alignment and calibration, variations in pitch and timing, possible tape stretching, print through and so on. Even well maintained studio tape machines operating within specifications can vary between machines and with the same machine from session to session.

That MCA claim is clearly then, snake oil. A bit like HD Tracks and others claiming their files are hi res when most are sourced from CD or analog tape sources, neither of which are
hi res'. Btw, the ability to reproduce frequencies (albeit imperfectly) which humans cannot hear does not make a medium hi res, rather it is the ability to produce or reproduce a sound with a high enough SNR, linearity of frequency response and low distortion/artifacts within the range humans can hear. Mark Waldrep explains this well.

Probably at least 50% of the music we listen to is sourced from analogue tape originally....not good enough for you ?..just askin.

 

[old tech]

Probably at least 50% of the music we listen to is sourced from analogue tape originally....not good enough for you ?..just askin.

I think you missed the point. It certainly is good enough, so how are perceived flaws in ADC conversion an issue when these flaws are far less, and by order of magnitude?

 

[Steve999]

I think you missed the point. It certainly is good enough, so how are perceived flaws in ADC conversion an issue when these flaws are far less, and by order of magnitude?

That's how I read it, like the two of you were on the same page but the wires got crossed somewhere.

 

[KeithEmo]

You can shout "bull" as many times as you like....

But, if you'd spend a little of that effort reading up on current signal processing technology, you would learn that those analysis tools do in fact exist, and that separating information from hoise, even when the noise is at a higher level than the information, is well established technology, as well as the theory that explains why and how to do it, and enables a good programmer to create new analysis tools that do specific things even more accurately. As a broad generalization, when you want to analyze something, you start by looking at ALL the information you have; you do NOT throw half of it away, while cheerfully exclaiming "I just know there was nothing useful in that half", then declare that anybody who disagrees with that absurd claim must be wrong.

It's pretty obvious, from even a cursory visual obsrvation of the one sample BigShot provided in that link, that those ultrasonic frequencies contain some sort of information... at least in the song he looked at. The "stuff" above 20 kHz looks nothing at all like random noise and, if it isn't random noise, then the only other possibility is that it's some sort of information.Therefore, the only questions that remain are exactly what sort of information is there, how we can extract or analyze it, and whether it might be useful for something.

If I have an instrument whose primary frequency is at 2 kHz...
- the level and phase relationship of the harmonic at 4 kHz provides information
- and the level and phase relationship of the harmonic at 24 kHz will give me MORE information

I'll gladly stop claiming that such things are possible....
Right after you show me a statistical analysis showing that, after analyzing a bunch of high-res recordings,
NOTHING in the spectral range above 20 kHz on any of them correlated in any way with any details about the instruments, the room, or the equipment involved.
(That would show that, at least with the currently available tools, there was really "nothing useful there".)
Until then, perhaps you should stop claiming to known the unknowable....

Will you PLEASE stop!! You respond to accusations of misrepresentations, fallacies and BS with just even more misrepresentations, fallacies and BS!
We have agreed that sometimes there is "stuff" in some recordings above 20kHz, which is precisely where we started! But where do you get the next bit from? There is ALWAYS some ultrasonic undifferentiated random noise and that's one of the big problems (or would be if it was audible!) that ultrasonic noise is constant or somewhat higher in level but the ultrasonic content of musical instruments is very much lower (or non-existent), making differentiation difficult or impossible.

2. BULLSH*T! Despite NUMEROUS requests you STILL have NOT provided even a shred of evidence that ANY acoustic information exists above 20kHz, let alone differentiable or even analysable acoustic information!
2a. What three or four echoes, you can't even show the existence of the first echo, let alone the next two or three which would be even lower in level!

3. So let me get this straight; you would filter out all the masses of acoustic information which actually does exist (almost entirely below 12kHz) and then boost and analyse the freq region where it doesn't?? That's some sort of audiophile logic and approach is it?

4. Not just BS but outrageous BULLSH*T! If you find it so easy, what are you doing here, you should be living on a super-yacht somewhere.



1. Great, so you're going to analyse what isn't there, with analysis tools that don't exist, so you can write something on your album cover. Now, what about the actual argument I'm refuting, that you could use that information in some futuristic system to correctly synthesise it's 3D place. Your also ignoring the fact that the plywood room acoustic information has been mixed with masses of other reverb information and how the hell are going to differentiate it from that? But heck, that's easy compared to trying to analyse acoustic information in a frequency range where it doesn't even exist!

2. Great, so you're going to pick out the plywood acoustics which are mixed with the violin (and other instrument) acoustics in a range where there isn't any acoustics. Have you picked out a super-yacht yet?

3. I presume you must be talking about an audiophile brain, if it can visualise a sound-stage from information that isn't even there and would be inaudible if it were?

4. Well knock me down with a feather!



1. Oh dear, right back to the BS: What do you mean "apparently"? Don't you know? Then why the hell don't you ask someone who uses it everyday, instead of arguing with them and just making up BS!!! What about WNS, the Sony Restoration Bundle, UnVeil, the Cedar forsenic kit and all the others? Like most others in my profession, I've spent tens of thousands of the years and use it everyday. I know exactly what it can do AND, what it can't!

2. What do you mean "new", we been doing that for god knows how many years. The newest software is better than the old but after many years development it's still only partially successful some of the time, with specific material, it's typically little more than just a starting point. At this rate it won't become an accurate autonomously tool until well after I'm pushing up the daisies, if ever! There still isn't even a scientific theory about how it might be done, let alone anyone trying to design an actual product. Once they figure that out though, maybe then they can figure out how to do it in a frequency range where there isn't any acoustic information to start with, who knows?

3. I know, I told you that about 3 pages ago!

G

 

[KeithEmo]

You clearly haven't read their claims (which, as I said, I do NOT necessarily believe to be substantiated at this point).

They claim that, by analyzing the digital version that was sourced from that master tape, they can identify specific flaws in the ADC used to perform the conversion.
(They are essentially identifying and analysing the artifacts of the flaws in the conversion process.)
Then, based on that information, they can apply "corrections" to that digital copy that cancel out those flaws, thus making a new master that is more accurate to the original.
(They are a little vague about whether they are claiming to identify the specific equipment involved... or simply to identify the TYPE of flaws, and apply a correction factor to cancel them.)

They are only claiming to be able to identify and correct flaws introduced during the actual conversion from analog to digital.
They are not claiming that their process will correct flaws that are present in the original master tape.

Possible? I doubt it. Even if it were possible where does it leave MQA files that were originally sourced from analog tape? How will they reverse engineer the by order of magnitude greater flaws around non-linear sonic signatures such as wow, flutter (and scrape flutter), imperfect alignment and calibration, variations in pitch and timing, possible tape stretching, print through and so on. Even well maintained studio tape machines operating within specifications can vary between machines and with the same machine from session to session.

That MCA claim is clearly then, snake oil. A bit like HD Tracks and others claiming their files are hi res when most are sourced from CD or analog tape sources, neither of which are
hi res'. Btw, the ability to reproduce frequencies (albeit imperfectly) which humans cannot hear does not make a medium hi res, rather it is the ability to produce or reproduce a sound with a high enough SNR, linearity of frequency response and low distortion/artifacts within the range humans can hear. Mark Waldrep explains this well.

 

[Steve999]

You can shout "bull****" as many times as you like....

But, if you'd spend a little of that effort reading up on current signal processing technology, you would learn that those analysis tools do in fact exist, and that separating information from hoise, even when the noise is at a higher level than the information, is well established technology, as well as the theory that explains why and how to do it, and enables a good programmer to create new analysis tools that do specific things even more accurately. As a broad generalization, when you want to analyze something, you start by looking at ALL the information you have; you do NOT throw half of it away, while cheerfully exclaiming "I just know there was nothing useful in that half", then declare that anybody who disagrees with that absurd claim must be wrong.

It's pretty obvious, from even a cursory visual obsrvation of the one sample BigShot provided in that link, that those ultrasonic frequencies contain some sort of information... at least in the song he looked at. The "stuff" above 20 kHz looks nothing at all like random noise and, if it isn't random noise, then the only other possibility is that it's some sort of information.Therefore, the only questions that remain are exactly what sort of information is there, how we can extract or analyze it, and whether it might be useful for something.

If I have an instrument whose primary frequency is at 2 kHz...
- the level and phase relationship of the harmonic at 4 kHz provides information
- and the level and phase relationship of the harmonic at 24 kHz will give me MORE information

I'll gladly stop claiming that such things are possible....
Right after you show me a statistical analysis showing that, after analyzing a bunch of high-res recordings,
NOTHING in the spectral range above 20 kHz on any of them correlated in any way with any details about the instruments, the room, or the equipment involved.
(That would show that, at least with the currently available tools, there was really "nothing useful there".)
Until then, perhaps you should stop claiming to known the unknowable....

This may be valid data as to instruments and their harmonics: http://www.zytrax.com/tech/audio/audio.html (go to the bottom of the page). I'm not competent to judge it, but I believe it. So the only thing you have up there above 20 khz is percussion harmonics that maybe a very small sliver of the population can hear a small portion of during the early part of their lives, if I am reading and understanding this right.

What do you think? Am I getting this right?

If I understand correctly a person here is saying they measure and then verify distant harmonics from the jazz drum kits above 20 khz in recordings by digitally modifying the pitch down into the audible range and amplifying it greatly. It sounds reasonable to me. The chart would indicate the cymbals and hi-hats can go up to 24 khz in the sixth harmonic. Again, I am not competent to judge the accuracy of this information. But the chart and the reported data seem consistent to me. To me the idea you have expressed of an instrument that plays a fundamental tone of 2 khz producing a 24 khz harmonic seems outlandish. It's just an uninformed guess on my part.

Do you think it's outlandish? Do you have any way to test it? It is you who are making the claim--that's standard operating procedure--to ask the person making the affirmative claim to offer proof. I'm not going into analogies, I'm just asking a dry question.

Can we agree on this--that the frequencies from musical instruments above 20 khz are of no use at all to the home consumer with today's technology? If I am reading things correctly and putting two and two together right, at Bigshot's request I listened to a file of just such information with headphones that are measurably demonstrated to produce the frequencies at least up to 22 khz without attenuation and I heard absolutely nothing at what would be ear-damaging volumes if there were any common audible musical content.

What about the idea that if you could hear these sounds just barely in isolation, they would be masked by anything resembling music. Would you agree with that?

We need to think carefully and organize your thoughts and hit it on the merits, and I think you need to accept that when you have made a claim it's up to you to prove it or else we would err under the circumstances that necessitated the creation of this sub-forum in trusting your bare assertion. We can argue as to who is making the claim as a matter of semantics, but it looks to me like you are making the affirmative claims here. If you think Gregorio is making an affirmative claim as to what can be done with certain information rather than negating your claims, let me know. He may well show you actual proof of the affirmative assertions he is making. I see him as doubting your claims, though. If so, it would be best and standard-issue protocol and rigor if you came forward with actual proof of your assertions. It's not really fair to ask someone to prove that they know or don't know the unknowable. If anything it is at least bordering on tautology that they don't know the unknowable.

Would you agree?

I think you know more than I do. Help me out here.

Honestly, I hope you will provide an informative response that I can enjoy as a learning experience and a good read. That is my hope.

(Edited several times for better clarity.)

 

[old tech]

You clearly haven't read their claims (which, as I said, I do NOT necessarily believe to be substantiated at this point).

They claim that, by analyzing the digital version that was sourced from that master tape, they can identify specific flaws in the ADC used to perform the conversion.
(They are essentially identifying and analysing the artifacts of the flaws in the conversion process.)
Then, based on that information, they can apply "corrections" to that digital copy that cancel out those flaws, thus making a new master that is more accurate to the original.
(They are a little vague about whether they are claiming to identify the specific equipment involved... or simply to identify the TYPE of flaws, and apply a correction factor to cancel them.)

They are only claiming to be able to identify and correct flaws introduced during the actual conversion from analog to digital.
They are not claiming that their process will correct flaws that are present in the original master tape.

Yes I understand that, I was just pointing out there are more flaws in playback from the analog source (ie from the tape machine converting the magnetic layer of the tape to an electrical signal) than in the ADC conversion.

Correcting 'flaws' in ADC conversion while ignoring the flaws from electro/magnetic/mechanical analog sources is like leveling out a slight undulation in the road while ignoring the pot holes.

 

[analogsurviver]

Possible? I doubt it. Even if it were possible where does it leave MQA files that were originally sourced from analog tape? How will they reverse engineer the by order of magnitude greater flaws around non-linear sonic signatures such as wow, flutter (and scrape flutter), imperfect alignment and calibration, variations in pitch and timing, possible tape stretching, print through and so on. Even well maintained studio tape machines operating within specifications can vary between machines and with the same machine from session to session.

That MCA claim is clearly then, snake oil. A bit like HD Tracks and others claiming their files are hi res when most are sourced from CD or analog tape sources, neither of which are
hi res'. Btw, the ability to reproduce frequencies (albeit imperfectly) which humans cannot hear does not make a medium hi res, rather it is the ability to produce or reproduce a sound with a high enough SNR, linearity of frequency response and low distortion/artifacts within the range humans can hear. Mark Waldrep explains this well.

First of all, nobody ever climed to be able to compensate for ALL deficiences of the analogue gear. The topic is ONLY removing/correcting for the artefacts caused by the digitalisation.

Well, then you should check HQ Player - as good as any starting point is https://www.computeraudiophile.com/forums/topic/19715-hq-player/
4 years later, only the one above knows just to which point in attaining the perfection with each and every ADC/DAC combination(s) known to be made sometime in history the latest incarnation or HQPlayer V.x.y.z addendum ž has arrived. Last time I checked ( looong ago... ), it required a computer solely dedicated eclusively to audio - min system requirement 24GB RAM ... and everything else at this or higher level.

MQA surely does similar things - only likely to be even more supported by the input from (m)any record companies that jumped on the bandwagon. If they actually allowed the devices they have been using to measure them, MQA team could actually devised correction(s) - for each and every one of those supplied. As record companies tend to use stock equipment, having analyzed one "Troublemaker MK3a" covers it and its use in all companies - it is enough to know whether the "Troublemaker MK3a" has been used in the process - or not.

Most probably algorhytms to hunt for particular artefacts could have been devised - and, of course, applied in the MQA process ....

I have a huntch MQA will get remembered, even if NOT for its prime intent/purpose, for its contribution to the digital processing - much as CD-4 quadrophonics did for the improvement in phono cartridges ( requirement of frequency response to 45 kHz ). CD-4 may well be commercially dead for decades now - but the improvement in phono cartridges ALSO FOR STEREO it did bring is very much still with us - and is, de facto, the root why we are having this conversation. Prior to the emergence of DSD64/aka SACD and at least 88.2 kHz PCM, phono playback was the ONLY mass supported medium capable of playing back content > 20 kHz.

And - whatever it is - it has been the reason enough many listeners prefer it over the RBCD.

 

[old tech]

First of all, nobody ever climed to be able to compensate for ALL deficiences of the analogue gear. The topic is ONLY removing/correcting for the artefacts caused by the digitalisation.

Well, then you should check HQ Player - as good as any starting point is https://www.computeraudiophile.com/forums/topic/19715-hq-player/
4 years later, only the one above knows just to which point in attaining the perfection with each and every ADC/DAC combination(s) known to be made sometime in history the latest incarnation or HQPlayer V.x.y.z addendum ž has arrived. Last time I checked ( looong ago... ), it required a computer solely dedicated eclusively to audio - min system requirement 24GB RAM ... and everything else at this or higher level.

MQA surely does similar things - only likely to be even more supported by the input from (m)any record companies that jumped on the bandwagon. If they actually allowed the devices they have been using to measure them, MQA team could actually devised correction(s) - for each and every one of those supplied. As record companies tend to use stock equipment, having analyzed one "Troublemaker MK3a" covers it and its use in all companies - it is enough to know whether the "Troublemaker MK3a" has been used in the process - or not.

Most probably algorhytms to hunt for particular artefacts could have been devised - and, of course, applied in the MQA process ....

I have a huntch MQA will get remembered, even if NOT for its prime intent/purpose, for its contribution to the digital processing - much as CD-4 quadrophonics did for the improvement in phono cartridges ( requirement of frequency response to 45 kHz ). CD-4 may well be commercially dead for decades now - but the improvement in phono cartridges ALSO FOR STEREO it did bring is very much still with us - and is, de facto, the root why we are having this conversation. Prior to the emergence of DSD64/aka SACD and at least 88.2 kHz PCM, phono playback was the ONLY mass supported medium capable of playing back content > 20 kHz.

And - whatever it is - it has been the reason enough many listeners prefer it over the RBCD.

Are you still on your vinyl horse? I only know a minority that prefer vinyl playback over RBCD in a general sense (ie excluding certain examples that are better mastered than the equivalent digital release) and even so, they prefer it because they find the distortions pleasant, rather than a fantasised belief that they have superman hearing of higher frequencies. Most rational people who understand audio as a science know that RBCD is a higher fidelity format than vinyl for all frequencies that we humans can hear. The only bandwagon are the marketing gurus that appeal to a certain type of audiophile (aka audiophools) with their psuedoscience. Unfortunately you get that in all industries, including medicine, finance etc not just audio.

In any event, your post is off-topic as the point is that comparing 'flaws' in ADC conversion with flaws in playback of an analog master tape before the DC conversion is like comparing molehills to mountains.

 

[analogsurviver]

Yes, I am still on my vinyl horse - or DSD128 ( present, hopefully DSD512 near future ) for actual recordings. I might even admit - shame on me - sometimes using 192/24 PCM for some purposes - but only because these purposes involve mandatory spectrum analysis and other computer mumbo jumbo - and therefore conversion from DSD to PCM, taking both additional time and storage place, better used for other purposes.

The point is that vinyl horse(s) can run at substantially different speeds, while running on the very same analogue record - whereas RBCD is inherently defined and by its definition, it is too slow.

I agree that marketing gurus are doing what you accused them of in all fields.

 

[Glmoneydawg]

I think you missed the point. It certainly is good enough, so how are perceived flaws in ADC conversion an issue when these flaws are far less, and by order of magnitude?

agreed....i managed to misread your post

 

[Steve999]

Yes, I am still on my vinyl horse - or DSD128 ( present, hopefully DSD512 near future ) for actual recordings. I might even admit - shame on me - sometimes using 192/24 PCM for some purposes - but only because these purposes involve mandatory spectrum analysis and other computer mumbo jumbo - and therefore conversion from DSD to PCM, taking both additional time and storage place, better used for other purposes.

The point is that vinyl horse(s) can run at substantially different speeds, while running on the very same analogue record - whereas RBCD is inherently defined and by its definition, it is too slow.

I agree that marketing gurus are doing what you accused them of in all fields.

I started an LP / vinyl thread a while back and no one posts to it. If you post to it I’ll cut you some breaks and back you up wherever I can. If you look way down the list of threads you’ll see it. For what it’s worth, I played vinyl for one of my kids for a while the other day and he was just in love with it. The sound is good and you are just so much viscerally closer to what’s going on. You can hear the music from the cartridge with everything off, you have an intuitive sense for the vibrations and the magnets and the electronic current, it’s amazing to hear it amplified and you’re just like, wow, if all you’ve heard is CDs or file formats your whole life. I for one have had the thought that if we had a sturdier LP substance, as in not scratching, or developing surface noise to such an extent, maybe there would be a lot more vibrancy to the format commercially. Even now, it’s just amazing and fun. I’m lucky enough to have a few hundred LPs—a small collection yes but enough to have some real fun. If you want to post to my thread we can hash these things out. You can tell me what the best sounding LPs are. I’d be interested in checking them out. I have a feeling old tech might jump in too.

It’s the fourth thread on the second page of sound science right now.

 

[Steve999]

Are you still on your vinyl horse? I only know a minority that prefer vinyl playback over RBCD in a general sense (ie excluding certain examples that are better mastered than the equivalent digital release) and even so, they prefer it because they find the distortions pleasant, rather than a fantasised belief that they have superman hearing of higher frequencies. Most rational people who understand audio as a science know that RBCD is a higher fidelity format than vinyl for all frequencies that we humans can hear. The only bandwagon are the marketing gurus that appeal to a certain type of audiophile (aka audiophools) with their psuedoscience. Unfortunately you get that in all industries, including medicine, finance etc not just audio.

In any event, your post is off-topic as the point is that comparing 'flaws' in ADC conversion with flaws in playback of an analog master tape before the DC conversion is like comparing molehills to mountains.

All of these analogies remind me of an old John Belushi SNL skit where he started off stating the common wisdom that Spring comes in like a lion and out like a lamb, or vice versa, I forget, and then he totally goes off on a litany of analogies he thinks are more appropriate, I’ll try to dig it up and add it from YouTube. The point being, once we are in debate mode I think it’s best to minimize the analogies, Getting into what analogy is best or why a certain analogy is being discussed doesn’t take us much of anywhere. It’s comical but not constructive, IMHO.

Here, this just cracks me up so bad. It’s the official NBC clip.

https://www.nbc.com/saturday-night-live/video/weekend-update-john-belushi-on-march/n33439

 

[analogsurviver]

I started an LP / vinyl thread a while back and no one posts to it. If you post to it I’ll cut you some breaks and back you up wherever I can. If you look way down the list of threads you’ll see it. For what it’s worth, I played vinyl for one of my kids for a while the other day and he was just in love with it. The sound is good and you are just so much viscerally closer to what’s going on. You can hear the music from the cartridge with everything off, you have an intuitive sense for the vibrations and the magnets and the electronic current, it’s amazing to hear it amplified and you’re just like, wow, if all you’ve heard is CDs or file formats your whole life. I for one have had the thought that if we had a sturdier LP substance, as in not scratching, or developing surface noise to such an extent, maybe there would be a lot more vibrancy to the format commercially. Even now, it’s just amazing and fun. I’m lucky enough to have a few hundred LPs—a small collection yes but enough to have some real fun. If you want to post to my thread we can hash these things out. You can tell me what the best sounding LPs are. I’d be interested in checking them out. I have a feeling old tech might jump in too.

It’s the fourth thread on the second page of sound science right now.

There are - at least - two LP/vinyl threads on head-fi, running for a long, long time :

https://www.head-fi.org/threads/tur...t-a-new-thread-ask-your-question-here.613136/

https://www.head-fi.org/threads/post-a-photograph-of-your-turntable.549616/

TBH - vinyl is LOTS of hits and misses - the latter outnumbering the former, unfortunately. It is an EXTREMELY metiuculous way of doing things - whereas one can be "sloppy" with digital ( and everything can be backed up and/or restored - at least for the last whatever operation you did wrong ) - but EVERY mistake with things vinyl is final. It can range from ruined just one record ( learning the hard way in the least expensive way... ), trough breaking styli ( at "few" hundreds to "few" K a pop... ) - to the harshest one - realizing you have SNAFUed your entire record collection to FUBAR condition ...

It is MUCH more expensive than digital. Unless you plan to have at very least approx 10K for your entire rig ( sky is the upper limit ) - digital will always be a better choice. Records are the second most expensive sound carrier commercially available - after R2R second gen tapes. Record hygiene is THE biggest issue - and nobody should be without some serious record cleaning "device(s)".

I work with analog records and the equipment to play them on for 43 years , have MUCH more experience than most analog oriented audiophiles, yet I know that I know only a little. That said, I forgot about analog record playback probably more than 99% of people will ever know.

Currently in the process of figuring out how to digitise some 2-3K records - in a way that will result in a digital file that should be better sounding than possible with normal record playback, even when using the best possible equipment. In essence, bringing the sensation your kid experienced for the first time with vinyl even further - on a digital file, all while preserving the vinyl for the future with the minimal possible record wear.

It is a tall order - but, as it seems, doable.