[KeithEmo]

I agree entirely... with two small exceptions.

"Proving that ultrasonics aren't important" would only "nuke their sales" if their sales were based largely on claims that their product had great ultrasonic performance.
That wouldn't be the case if they really just sold their products based on the claim that "they sound good".
(Which is why it's a good idea to avoid products whose "claim to fame" is based on one questionable virtue.)

I should also point out that this is far more the case for some products and situations than others.
For example, we would expect sales of high-resolution files, claimed to be better in part because of ultrasonic performance, would drop if that was proven to not be significant.

However, I doubt that sales of DACs that support 192k would be affected at all.
The reason is that most current DACs support 192k.
Therefore, while someone may NOT buy a certain DAC because it DOESN'T support 192k...
It's really doubtful that any company "sells more DACs because they support 192k".
We say that "for DACs 192k is NOT a product differentiator" (it was ten years ago - when few DACs supported it - but not now).

For DACs, 192k is what we in the industry call "a check box item".
It's on the list of what people expect and look for when selecting a product.
They don't select a particular product because it HAS that feature...
But they will AVOID a product that LACKS it (because they see it as a sort of standard feature)...

Nobody buys a car because it HAS air conditioning; because almost all cars have it...
But people will avoid buying a car that DOESN'T have it...
(So proving that air conditioning is useless to you because you live in Alaska won't really hurt sales of a car that has it.)

The other thing I would point out is that such a result won't nuke sales.
If the company conducted the test themselves, and the results would be bad for business, they simply won't publish it.
(What you suggested would only be the case if that company sponsored an independent test - which everyone agreed would be published regardless of the results.)

Earlier ITT we discussed the fact that most audiophile-oriented companies don't have any logical incentive to publish results on these topics. If consumers already believe the products have high performance, then proving ultrasonics are important won't affect sales. Proving ultrasonics aren't important would nuke their sales. Most companies that could afford to run the tests fall into the category of "consumers believe they have high performance"... so you see why nobody actually does the work.

Also a really rigorous, put-the-final-nail-in-the-coffin test would be expensive. My guess is no less than $250K to do it truly properly. $250K is not chump change for most audio companies, particularly for a project that is only of academic interest.

Keith (or I, or some other MOTT) could spend a work day at his desk testing these things with... himself... probably, but there isn't much point in doing that, it wouldn't be considered authoritative by anyone.

Others have also pointed out that, according to any reasonable approach to audio among academics, recording formats are basically a solved problem. The importance of frequencies over 20khz is - if anything - very low. There are more pressing research problems in the world of human hearing, like figuring out how to treat tinnitus, or how to prevent hearing damage, things like that.

 

[bigshot]

As long as we all agree that super-audible frequencies in music are super-fluous. But there are certain people who make a lot of money from selling inaudible sound. They have a vested interest in keeping this conversation going. There are also people who fervently believe that their ears can hear what normal human ears can't. They would rather talk about it in "pure theory" than submit themselves to a controlled test and find out that their ears aren't quite so golden. There's a lot of money to be made in helping these people stay in the dark.

 

[KeithEmo]

Thank you.

The biggest limitations on audio quality these days are probably:
1) transducers (speakers)
2) the room (the acoustics of the playback room itself)
3) production values

However, there really aren't many interesting tests being conducted on those subjects lately.
(How about a survey to determine how many people really prefer multi-track recordings to relatively unprocessed ones?)
(Or how abut some serious discussion about which reflections it's most important to eliminate when adding a limited amount of sound treatment to a listening room?)

Sadly, or maybe not, not too many people on this forum would really enjoy a scholarly discussion of woven carbon fiber vs parallel fibers in midrange cone construction....
(Or even a scientific discussion about the relative merits of Dirac Room Correction vs Audyssey....?)

I think the real problem is a disconnect on this proposition.

Keith (and I personally) and a few others find ultrasonics fun to think/talk about, regardless of whether there's any practical application today.

This is mostly because they're the only thing you can discuss materially improving in audio without getting deep into like... materials science and mechanical engineering. Back here on planet earth, 2018, as far as most reasonable people are concerned, the biggest bottleneck in audio reproduction today is transducers, (and acoustics) and talking about how to improve transducers beyond today's state of the art is frankly above my pay grade. And acoustics is sort of boring and out of place on this forum because it's more of a woodworking project than "audio" most of the time.

Others find them annoying to think about or talk about because there's no practical application today. So those others argue against Keith as if he's advocating for something in particular, when really he's just (as I read it) more on a "wouldn't it be interesting if..." sort of trip.

 

[KeithEmo]

How about if we just agree that we DON'T all agree about that...
But there are lots of other things to talk about?

It's really cool to suggest that "everything should be properly tested"....
But, unless you have an endless wallet to pay for those tests, we may have to accept that it may not happen.
However, we do NOT live in a world where everything that hasn't been tested is assumed to be untrue.

Did you know that many foods and medicines currently in use were "grandfathered in", and so have never actually been tested for either safety or efficacy?
(The FDA did NOT go back and test every product that was already on sale when the agency was started.... it just wasn't practical.)

As long as we all agree that super-audible frequencies in music are super-fluous. But there are certain people who make a lot of money from selling inaudible sound. They have a vested interest in keeping this conversation going. There are also people who fervently believe that their ears can hear what normal human ears can't. They would rather talk about it in "pure theory" than submit themselves to a controlled test and find out that their ears aren't quite so golden. There's a lot of money to be made in helping these people stay in the dark.

 

[bigshot]

The problem here is that there's too much talking and not enough being talked about. I'm interested in discussing audiophile myths that have been disproved by controlled testing. There are an awful lot of those, and it is the topic of this thread after all. However the thread keeps getting derailed into discussions of "pure theory" that smells like more audiophile myths being peddled. I feel the need to interject a raspberry whenever I hear people "having fun" discussing things that just aren't true in the real world. Snake oil in "pure theory" is still a scam, and turning a blind eye to it "just for fun" is still being complicit in it.

I do a controlled test on every piece of equipment I buy. It doesn't take a lot of time, and it doesn't cost a lot of money. I understand why manufacturers might want to discourage this sort of thing though. It isn't good for business.

 

[Zapp_Fan]

@KeithEmo I can at least say that IMO the primary reflection points relative to the listening position are the most important to treat. You can do this literally by having someone walk around with a mirror held near the wall while you sit in the listening position, and mark anywhere you can see a speaker in a mirror.

Of course... acoustics is a deep enough topic to warrant its own forum, let alone thread, but if you want to know which spots are the highest priority, that's one way to do it

As far as high-res performance not nuking sales, I tend to agree with your assessment, it's a parity feature for a DAC at this point.

@bigshot - I have no illusions about me or anyone else being able to hear >20khz tones, but like Keith, I don't believe all nails are fully into the 44Khz coffin yet, or at least, I haven't seen the test that proves it yet. There are other types of information which may have some (modest) value in that frequency band which I haven't seen are completely debunked. Yet. I'm not saying they won't be, I just don't happen to know that they are.

Of course I always acknowledge that they're mostly irrelevant, especially with today's recordings and gear, but like I said, I just think it's fun to think about.

 

[bigshot]

I have no illusions about me or anyone else being able to hear >20khz tones, but like Keith, I don't believe all nails are fully into the 44Khz coffin yet, or at least, I haven't seen the test that proves it yet.

If you'd like to do a test yourself to find out, I would be happy to share my experience doing that test myself. It is very easy to do and then you would know. Not asking questions isn't a good excuse for not knowing answers.

Why is it that the regular folks in Sound Science do listening tests and members of the trade don't? It's curious.

 

[Zapp_Fan]

If you'd like to do a test yourself to find out, I would be happy to share my experience doing that test myself. It is very easy to do and then you would know. Not asking questions isn't a good excuse for not knowing answers.

Why is it that the regular folks in Sound Science do listening tests and members of the trade don't? It's curious.

I actually think it's a really hard test to do and I don't know if I own any equipment capable of doing a valid test. I mean ... even to find a recording or two where the cymbals (or breaking glass or whatever) aren't just totally submerged in noise would be a project in and of itself. You might even need to make the recording yourself, another big project. Then to be 100% sure your gear can produce ultrasonics with something like decent fidelity without really being able to hear it ... also hard.

Basically I don't have much confidence that the right materials and setups are actually easily accessible or affordable, and as a MOTT, I don't have a budget for this test, nor do I think I'll have one next year or the year after. I'm only participating because I actually enjoy the useless theoretical discussion. My fiancee won't humor me so it's up to you guys.

I do a lot of listening tests... for work. They are mostly focused on frequencies below 16khz. No shame in this game.

 

[Phronesis]

I'm still generally on break, but wanted to share this, in case it hasn't been shared before (I don't remember):

https://tapeop.com/blog/2018/08/30/subconscious-auditory-effects/

It may have some relevance to the current topic of ultrasonics, and perhaps worth keeping in mind that the boundary between sonic/ultrasonic varies a lot between people. 18 kHz may be consciously perceivable for one person, only subconsciously perceived by another, and neither consciously nor subconsciously perceived by another.

 

[bigshot]

I actually think it's a really hard test to do and I don't know if I own any equipment capable of doing a valid test.

Do you have an SACD player? All you need is an SACD recorded in native DSD and with a redbook layer that is the same mastering. I can point you to the one I used if you want. Aside from that, it's just a preamp and switcher.

 

[Zapp_Fan]

Do you have an SACD player? All you need is an SACD recorded in native DSD and with a redbook layer that is the same mastering. I can point you to the one I used if you want. Aside from that, it's just a preamp and switcher.

Don't have any of those things handy. I have a DAC that may do 96khz, but I sincerely doubt its analog ouputs are any good up past 20khz. Also, we'd have to independently establish the noise floor of each piece of gear at / above 30khz, etc. Not to mention find some transducers that are actually good > 30khz, again, probably not trivial. I have some Blue Sky monitors and I have some ER4XRs and (although they are wonderful) I don't think either one would be worth a crap for this test.

I mean, I can tell you right now none of my gear that I already own is likely up to the task. There's no question that ultrasonics are worthless in the context of things I own and things I actually listen to. But that's not the question I am interested in.

 

[bigshot]

I have a spare SACD player I could lend to the project. If it's an SACD player it's designed to reproduce super audible frequencies. If it's an SACD recorded in native DSD, it would have a full complement of ultrasonics. I also have a set of Oppo PM-1s that are rated to 50kHz in free field that I could conceivably loan. (I doubt we'd be running into much that high though.) This is the equipment I used to set up my own listening test. (I also did a test at my friend's studio with his pro reference rig.)

But if you think the only way to reproduce super audible frequencies is to use specialized equipment, then we've answered our question. They are irrelevant to the playback of recorded music in the home.

 

[Phronesis]

Recent article on ambient ultrasonics:

https://www.livescience.com/62533-ultrasonic-ultrasound-health-hearing-tinnitus.html

Doesn't seem that ultrasonics are necessarily something we'd want to capture in reproduced music. Seems plausible to me that at least some people might enjoy music more without ultrasonics.

(Yes, I know, supposed to be on break. I'm taking a break from being on break.)

 

[Steve999]

Recent article on ambient ultrasonics:

https://www.livescience.com/62533-ultrasonic-ultrasound-health-hearing-tinnitus.html

Doesn't seem that ultrasonics are necessarily something we'd want to capture in reproduced music. Seems plausible to me that at least some people might enjoy music more without ultrasonics.

(Yes, I know, supposed to be on break. I'm taking a break from being on break.)

Don't worry about taking a break from being on break! Just don't take a break from being on break from being on break and you're good!

 

[castleofargh]

I'm still generally on break, but wanted to share this, in case it hasn't been shared before (I don't remember):

https://tapeop.com/blog/2018/08/30/subconscious-auditory-effects/

It may have some relevance to the current topic of ultrasonics, and perhaps worth keeping in mind that the boundary between sonic/ultrasonic varies a lot between people. 18 kHz may be consciously perceivable for one person, only subconsciously perceived by another, and neither consciously nor subconsciously perceived by another.

this is the basic principle and as far as we know, how we hear. just that the apex area of the basilar membrane is in fact wider than the base, and the extreme values are kind of BS, but the graphs on the right help understand what I'm trying to say, so I show this one^_^. any vibration with a strong enough intensity can reach that area and shake the hair cells enough to trigger some electrical impulses. in fact you could even just have something shake the head regardless of what goes on in the ear canal, and still successfully trigger "hearing"(like bone conduction and stuff like that, which are really all just about shaking the hair cells enough to activate them).
now the cells "detecting" high frequencies are at the base, I have never seen anything challenging that tonotopic map of the receptors(given tones related to a position in the ear, and later to a position in the brain). when you send high freqs, the base is narrow and stiff and a rapid vibration is rapidly attenuated(if it wasn't already while traveling to get there inside the head). so high frequencies will significantly shake the entrance of the basilar membrane(the bigger the amplitude the bigger the area that's going to shake, but the resonance is going to be at the entrance.

now if we have a 2khz vibration, it will propagate further down and resonate wherever the shape create the resonance for 2khz. the hair cells in that area will be shaken more than the rest but everything from the base to that 2khz area is also shaking, and then the vibration will get reduced and probably won't shake anything in the area for low end frequencies.


a 60hz tone now. it will create a traveling wave all the way down that hopefully will still reach a place where it resonates so we can identify it by its tone(although that low we start to have the body shaking to go with it anyway).

on the B C D examples in the graph, despite the caricature and the tube being straightened up, what is true is how the base tends to shake significantly no matter the frequency of the tone. that is the reason why that's where we usually lose our hearing the fastest. stronger amplitudes and all sounds causing movements. but the implication is also that when you have a mix of signals, for the 19, 20 or 25khz to be identified for what it is, we cannot afford to have the rest of the music creating bigger vibrations at the base of the basilar membrane. otherwise we get masking, the same way we get it in frequencies close to the resonance point of any tone. if a tone is 5khz, it will resonate massively in the 5khz area and that will also shake things directly next to that area, even though it won't resonate like at 5khz. so if at the same time we have a 4.5khz signal, but the amplitude of the shaking even at the resonance point is still smaller than the shaking from the 5khz bringing each sides for the shaky ride, then we have no way of knowing that the 4.5khz tone even existed. it is masked.
this can happen for ultrasonic and probably for a bunch of the higher treble freqs too, when almost any other tone played at the same time. it's all a matter of amplitudes(how loud it is, and how well it will be carried into the ear. as after all, our sensitivity changes a good deal for very low and very high frequencies).

so we need:
- the ultrasonic content to be recorded without much attenuation from distance or the mic rolling them off.
- same thing for playback gears. while it's not hard to find headphones with stable and extended ultrasonic content, that may not be what we own.
- we need to have ears with that area not damaged so much that it's either dead or firing signals all the time as noise(which does happen in small proportions everywhere even for "good" ears, explaining in part why we do have hearing thresholds in the first place, the other reason being how neurons don't necessarily activate with any level of signal they receive).
- those ultrasonic signals to reach the cochlea and still have enough amplitude to shake things around the base of the basilar membrane.
- and that needs to be bigger than all the already occurring shaking at the base, caused by the rest of the music. because those cells can't possibly identify such frequencies with the period of the vibration, the cells are rather slow to reload once they have fired(I'm guessing potassium and whatever else like in almost everything electrical in the body). I remember watching a video with a guy measuring individual hair cells potentials from rat ears or whatever, but I can't find it when I need it.there was a lot to learn from, and also a few mysteries.

can we get all that? yeah it's possible, young with the right gear and the right track, and maybe we'll perceive all that. and maybe even when we don't notice consciously, our brain will subconsciously. but let's just agree that the chances aren't on ultrasounds' side.