Two Old ESS Talks

[pozz]

Most likely this: Upper Limit of Frequency for Human Hearing (R. J. PUMPHREY) which unfortunately is not publicly available. Some of the content is discussed on stackexchange.

It is one page like @gene_stl said. Author claims that using bone conduction he and two other individuals were able to hear up to 100kHz. He concludes that airborne sound is limited to around 20kHz because the middle ear fails to transmit higher frequencies, although the cochlea itself is still sensitive.

Edit: Published in 1950 by the way.

 

[pozz]

Mallinson was probably referring the Oohashi paper published in 2000: https://www.ncbi.nlm.nih.gov/m/pubmed/10848570/

It generated a lot of excitement at the time but was discredited as far as I know.

There's also a more recent article from 2014 by Oohashi's colleagues: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4005747/

No description of playback equipment that I can see.

 

[anmpr1]

When I see an D/A for $6,000 I lose interest immediately.

... top two channels have been driven by Pioneer M-22 Class A amp/toasters. I am seriously considering cashing those out while the cashing is good. Before the audiophiles get wise. It does measure like a high grade preamp.

It's clear that a well built SOA pro DAC can be had for under 2 (Matrix EX), or well under that (Benchmark DAC 3B). If you need analog preamplifier features there is the DAC 3 HGC ($2200.00), or something full blown like the HPA4/DAC 3B which would be $4700.00. If you don't mind the el-cheapo look, then there's the real bargains like Topping.

A Resonessence Invicta Pro will set you back $6000.00. It has fewer features than the HPA4/DAC 3B combination. Who knows? It may even be 'technically better' than Matrix or Benchmark. I have not seen a real review of it. Darko says it has "composure when delivering boisterously dynamic techno", is "clean and glossy" and "deals more in straight talk" than other DACs. If anyone understands what the hell any of that means, and if those things are what you are looking for, then I guess the Invicta Pro is your DAC.

PS: I'd keep the M22. Where else are you going to get something that cool looking? And in winter, it should help with your heating.

 

[tmtomh]

Mallinson was probably referring the Oohashi paper published in 2000: https://www.ncbi.nlm.nih.gov/m/pubmed/10848570/

It generated a lot of excitement at the time but was discredited as far as I know.

There's also a more recent article from 2014 by Oohashi's colleagues: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4005747/

No description of playback equipment that I can see.

As far as I can tell, every study or online comment that cites research in support of humans' ability to hear ultrasonics, cites Oohashi. And as you note, Oohashi has flaws and never has been replicated.

 

[anmpr1]

Mallinson was probably referring the Oohashi paper published in 2000: https://www.ncbi.nlm.nih.gov/m/pubmed/10848570/

It generated a lot of excitement at the time but was discredited as far as I know.

There's also a more recent article from 2014 by Oohashi's colleagues: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4005747/

No description of playback equipment that I can see.

This is damned interesting. One thing is clear, if your musical taste turns around Gamelan orchestral music played by Bali Island, Indonesian folk musicians, then you definitely want to look in to this. [This was the music presented in order to determine the so-called 'hypersonic effect'.]

Gear used was a "Direct Stream Digital (DSD) format having a sampling frequency of 5.6448 MHz. The electrical signal contained a wealth of HFCs, (high-frequency components) even reaching 100 kHz and above."

The ultra HF component was reproduced by TAD (Pioneer) PT-R9 ribbons.

Results were graphed from Alpha-2 electroencephalogram (EEG) signals. One intersting finding:

In these experiments, the total power of sound was always larger in LFC+HFC than in LFC alone. Thus, it is possible to assume that changes in Alpha-2 EEG are related to the total power of applied sound rather than to frequency.

But this was not an exact correlation, based upon differences in EEG response to differing HFC.

What can we say? At my admittedly lay level, we can say that A) if you like Javanese percussive instrument music, B) if you have HF ribbons going out to 125KHz (as the TADs are rated at), and C) have an EEG at home and don't mind the wires hooked up to your skull, then you might be able to detect a difference on the paper EEG printout you get while listening.

What I didn't see in the paper was any subjective rating, asking the participants whether they 'heard' or even 'felt' any physiologic change, either auditory or otherwise.

In any case, this is certainly an interesting thing. How it is related to home audio is something I can't relate to, at this time.

 

[Ilkless]

This is damned interesting. One thing is clear, if your musical taste turns around Gamelan orchestral music played by Bali Island, Indonesian folk musicians, then you definitely want to look in to this. [This was the music presented in order to determine the so-called 'hypersonic effect'.]

Gear used was a "Direct Stream Digital (DSD) format having a sampling frequency of 5.6448 MHz. The electrical signal contained a wealth of HFCs, (high-frequency components) even reaching 100 kHz and above."

The ultra HF component was reproduced by TAD (Pioneer) PT-R9 ribbons.

Results were graphed from Alpha-2 electroencephalogram (EEG) signals. One intersting finding:

In these experiments, the total power of sound was always larger in LFC+HFC than in LFC alone. Thus, it is possible to assume that changes in Alpha-2 EEG are related to the total power of applied sound rather than to frequency.

But this was not an exact correlation, based upon differences in EEG response to differing HFC.

What can we say? At my admittedly lay level, we can say that A) if you like Javanese percussive instrument music, B) if you have HF ribbons going out to 125KHz (as the TADs are rated at), and C) have an EEG at home and don't mind the wires hooked up to your skull, then you might be able to detect a difference on the paper EEG printout you get while listening.

What I didn't see in the paper was any subjective rating, asking the participants whether they 'heard' or even 'felt' any physiologic change, either auditory or otherwise.

In any case, this is certainly an interesting thing. How it is related to home audio is something I can't relate to, at this time.

It is very likely the results were the result of audible intermodulation that Oohashi did not control for. Here are two studies on this: one was a AES conference paper, the other was by David Griesinger (ex-Harman/Lexicon Chief Scientist).

 

[anmpr1]

It is very likely the results were the result of audible intermodulation that Oohashi did not control for. Here are two studies on this: one was a AES conference paper, the other was by David Griesinger (ex-Harman/Lexicon Chief Scientist).

That may be. After all is said and done, my takeaway is that I'd sure like a set of TAD super HF ribbons.

I wouldn't even hook them up. I'd just put them on the coffee table with the Architectural Digest, and when my audiophile friends came over and asked, I'd say, "Yep. These babies are flat to 125!" LOL

 

[Krunok]

As far as I can tell, every study or online comment that cites research in support of humans' ability to hear ultrasonics, cites Oohashi. And as you note, Oohashi has flaws and never has been replicated.

Which only means his study should be discarded.

 

[Vincent Kars]

Independently they are silent, but the mix clearly produces audible distortion

Probably IMD

The 2 test tones 19+20 kHz generate IMD and as you can see it generated spikes on both sides.
The ones at the left are within the audible range and when loud enough indeed audible.

 

[Eirikur]

Probably IMD

The 2 test tones 19+20 kHz generate IMD and as you can see it generated spikes on both sides.
The ones at the left are within the audible range and when loud enough indeed audible.

Thanks, nothing beats an actual measurement

Could you try the same with the two tones I used (F10/22350.61Hz and E11/42192.33Hz)?

I chose those specifically as they are both on the chromatic scale and exactly within the Nyquist cutoff band for 44100. As a bonus they are dissonant when played together (a minor second).

 

[anmpr1]

It is very likely the results were the result of audible intermodulation that Oohashi did not control for. Here are two studies on this: one was a AES conference paper, the other was by David Griesinger (ex-Harman/Lexicon Chief Scientist).

The Griesinger paper does not cite Oohashi, but is valuable nevertheless. It was done [2001] with gear that would be considered obsolete, today. This does not invalidate his findings, within his overall context. Nor does the Xiph dot Org link, but ditto it's value.

Martin Colloms' [2006] paper discusses Oohashi, and reports on both of O's papers. Correctly indicating that none of the test subjects could 'hear' the HF content alone, but were able to subjectively identify it when mixed with the 'audible' program material. Intermodulation distortion? Oohashi et al do not pinpoint (or really discuss) any possible electro-acoustic 'mechanism' responsible for their peculiar findings, nor do they have any concrete physiological-based explanation for the EEG/PET scan findings.

...we cannot conclude that the neural mechanisms incorporating ultrasound hearing, including the bone-conducting auditory pathway, are the system responsible for the hypersonic effect, which involves the brain stem and thalamus. These regions showed decreased activity compared with the baseline when HCS was presented and thus may not belong to the conventional auditory perception system. Therefore participation of nonauditory sensory systems such as somatosensory perception also needs to be considered in further investigations.

If (and it is a very big if) ultrasonic [Oohashi team calls it 'hypersonic'] signals have a physiological effect on humans, an effect that is not 'heard' but somehow influences our physiology, then the question is raised, what about all the ultrasonic garbage that is present in the natural environment? And how do they affect daily life, if at all?

However it is, none of this would seem to have any bearing at all for designing a competent DAC. Or setting up a hi-fi system. It could, however, sell a few more rolls of Reynold's Wrap than would otherwise be the case, to those living on the borderline of audio-neurosis.

 

[Julf]

And as you note, Oohashi has flaws and never has been replicated.

A Japanese team tried to replicate it (really tried, they didn't want to deal with the loss of face of proving Oohashi wrong) and failed.

 

[gene_stl]

I have in my vinyl collection a nice Gamelan record from Nonesuch called "Golden Rain" . Since it is "merely" vinyl I am sure all that wonderful ultrasonic hash isn't there. A nice album to listen to every 15 years or so.

If you can supposedly hear ultrasonics by bone conduction then wouldn't having your teeth cleaned by a hygienist using an ultrasonic scaler, be a very painful auditory experience. I wonder what kind of transducer Pumphreys used. I don't have the reprint yet.

I have taken part in studies at Washington University's Central Institute for the Deaf, wherein they were working on algorithms and software for cochlear implants. They put you in a functional MRI scanner and pipe audio to you using long plastic tube ear pieces. You hear things like backwards sounding and interfered with speech. You don't have to try to interpret them because they are looking at your thoughts and can tell whether you understand or not. very amazing. Such a study as Oohashi's would need to be done with fMRI. I think EEG would be close to useless. PET might tell you something. But in all cases "what" is indeterminate.

When I read about the Oohashi article and the criticism of it , i thought of my rather long career in implanatable medical devices. Companies always find a "heavy hitter" and pay him to go out and shill for them with other doctors. It's a very old story. In medical device industry and pharmaceutical these guys are just a fact of life and usually nobody tries to replicate their results except competing heavy hitters for competitive companies. Makes for some amusement at meetings. They are usually just ignored by the "real" scientists. iirc Oohashi was publishing outside of his usual area of work.

Finally I remember fleeing certain stores because the ultrasonics were causing me annoyance. Hasn't happened in ages , seems to have been a phenomenon of the seventies and eighties.

 

[anmpr1]

A Japanese team tried to replicate it (really tried, they didn't want to deal with the loss of face of proving Oohashi wrong) and failed.

Are you saying it's fake? FAKE! What about the EEG? How can you fake an EEG? It's like Jesse Ventura said when asked about pro-wrestling being a work: "How can you fake a body slam? You want to know the real fake sport? It's baseball. Haven't you ever wondered why the inning ends right when it's time to air the commercial!" /sarc

But seriously, that's the point of method. You present results, and others either verify it, or not. If they can, you progress. If not, you move along to something else. What's crazy are all the mystical stuff supposed to support audio-nervosa. Everything from Heisenberg Uncertainty to weird and unexplained electromagnetic influences. Truth is, it's easy to fool yourself.

 

[pozz]

I'm not sure of the basis or motivation for Oohashi's studies since HF perception is an anatomical limitation based on the length and dimensions of the cochlea and the basilar membrane.

Donald Greenwood did the main work in this area. It's his data that determined how implants would work.

 

[Julf]

I'm not sure of the basis or motivation for Oohashi's studies

Motivation? Oohashi pushed all sorts of "hypersonic" art and devices he had designed. His degree was in agriculture, but he became sort of a cult hero. "While he is a composer, conductor, and producer, as a scientist he has interests including environmental science, information science, Kansei engineering, production engineering, molecular biology, artificial life, and anthropology."

 

[gene_stl]

 

[Eirikur]

Thanks @gene_stl for digging up this nugget.

That also settles the test "methodology" and the lack of repeatability

 

[anmpr1]

There is research on-line relating to this stuff. I've cited two, below. Ultrasonic 'perception' is established, but its application to normal hi-fi audio is vague and tenuous. I'd say it has no application at all. My admittedly lay investigations show that 'perceptions' of frequencies up to at least 100 KHz are possible under very specialized (direct bone conduction) laboratory conditions. However, perceptions are not 'hearing' in the normal sense of the word.

A) Although testing of higher frequencies with bone-conduction is rare and unstandardized, Corso [Pitch Discrimination at High Frequencies by Air and Bone Conduction, American Journal of Psychology, V. 78, 1965.] measured bone-conduction thresholds at higher frequencies with procedures similar the ISO statndards, but did not have any masking stimuli. Furthermore, bone-conduction may facilitate sensitivity to sounds even higher in frequency than can be detected through air-conduction, possibly up to 95KHz. [Thresholds of Audibility for Bone-Conduction Headsets, Walker and Stanley, Sonification Lab, School of Psychology, Georgia Institute of Technology: Proceedings of ICAD 05-Eleventh Meeting of the Internation Conference on Auditory Display, July 2005.]

B) Humans can detect ultrasound up to at least 100 KHz, but perception generally requires direct contact of the source with the body. Ultrasound sets the brain into forced vibration, and it is the brain oscillation that is detected on the base of the cochlea in normal hearing individuals. With hearing loss, greater ultrasonic energy is needed to spread the displacement on the basilar membrane toward the region of intact hair cells. Ultrasonic pitch is not related to the stimulating frequency, but rather to the remaining high audio frequency ability of the listener. [Ultrasonic Hearing in Humans: Aplications for Tinnitus Treatment, Lenhardt, Department of Otolaryngology, Virginia Commonwealth University, International Tinnitus Journal, Vol 9 No2, 2003.]

It must be noted that what is described is an in-band perception of an out of band vibratory stimuli 'bleeding' into the normal hearing range. It has nothing to do with ultrasound high frequencies somehow extending our normal hearing to outer limit ranges, or making what is heard within the normal range of hearing 'better'. It appears that 'ultrasonic' mechanisms may show some benefit within a medical context, for example in the treatment of tinnitus, but as far as anyone benefiting from ultrasonic frequencies as they might relate to their hi-fi system? Well... that is not a conclusion that can be supported by these studies. At least as I understand them. Again, if someone else has more information, I'm happy to learn from them.

 

[gene_stl]

B) Humans can detect ultrasound up to at least 100 KHz, but perception generally requires direct contact of the source with the body. Ultrasound sets the brain into forced vibration, and it is the brain oscillation that is detected on the base of the cochlea in normal hearing individuals. With hearing loss, greater ultrasonic energy is needed to spread the displacement on the basilar membrane toward the region of intact hair cells. Ultrasonic pitch is not related to the stimulating frequency, but rather to the remaining high audio frequency ability of the listener. [Ultrasonic Hearing in Humans: Aplications for Tinnitus Treatment, Lenhardt, Department of Otolaryngology, Virginia Commonwealth University, International Tinnitus Journal, Vol 9 No2, 2003.]

This is how it seems to me, but it is not really my area of expertise. ( Several times I had tried to get positions selling cochlear implants but it never happened.)