'Life Above 20kh' Research Paper, Harmonics (Overtones)


I happened across this study about sound frequencies beyond 20kh. Harmonics (I prefer the term Overtones)

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

Aside from the study’s purpose, skimming the text is fascinating, sends my/your inquisitive mind in many directions.

Think about your listening room when reading his extremely detailed measurements to ascertain/eliminate any external contributions to his measurements.

Check out the amount of sound energy beyond 20kh of various instruments, crash cymbals particularly revealing. Jangling keys also a surprise.

The comments about a Piano’s Altered Harmonics including the strings/sound board/floor, I found surprising. I’ve always known how difficult it is to record a piano, this must be part of the challenge.

Even though test subjects say they cannot hear the super tweeter, experimenters could measure that the super-frequencies were detected by ..... , awareness and the brain’s perception ability are different things
..................................

Overtones. ’Analog Gets the Overtones Rght’.

I’ve often said, after a whole lotta years, the only way I can begin to explain why I prefer analog, is ’Analog Gets the Overtones Rght’.

Reel to Reel, my noisiest format, is my most preferred source. LP favored over CD. Tubes over SS. Myself, and ANY/EVERYBODY listening here to comparisons over the years has the same preferences.

More reason to get our ears professionally cleaned!!

Elliott




elliottbnewcombjr
First of all this paper proves absolutely nothing. It brings up some interesting avenues for research which is about it. One tenet od scientific research is that the results have to be reproducible. No body has reproduced anything.
Music is absolutely not just heard but experienced. Anybody with good subwoofers knows that. Then there are the visual aspects. In spite of the sound being butte awful in many live venues the thrill of seeing a live performance frequently (but not always) overcomes that problem. Sitting at home staring at loudspeakers distorts the sound stage. Close your eyes and instrument size and location becomes better defined. Playback of a good concert video (with a big screen between the speakers takes it up another notch.
As for ultrasonics ? Very few speakers do much above 20 kHz. If they do it is so focused that you would have to be directly in front of and at the level of all the tweeters to be exposed to it. Anybody experienced in reading EEGs will tell you that it is absolutely impossible to draw a conclusion like this from these tracings. There are types of brain imaging that would be more likely to tell you something. We know for instance that people blind from a young age transfer their visual cortex to sound interpretation instead. Stevie Wonder is such an example. 
Any of the examples above of people preferring one type of amplifier over another are purely anecdotal and do not mean much. Many amps considered in the group of "best made" are solid state. I have never seen anybody drive subwoofers with a tube amp. There are great tube amplifiers and I have no doubt they can be very compelling with certain types of loud speakers. 
If anything, broad band performance influences performance in the audio band in a positive way. I know in my experience amps that go down to DC make better bass even though there is nothing audible below 18 Hz. 
As for vinyl my own pet theory is that there is something about the low level background noise that biases of dither's our brains. Just a thought. 
So if CD quality is 44.1 kHz and based upon 20 - 20,000hz.
Higher sample rates are still (as far as I know?) still from 20-20,000hz,but those sample rates could be easily quadruple that with modern bandwidths and technology.

Is it plausible that recordings that are captured through a broader frequency range (than considered hearing range), requiring a higher sample rate could bring digital closer to or even as good as analogue?

I have read about how engineers arrived at the sample rates for CD for example, and the OP has posted a paper that may question the basis for the sample rates, that it was an oversight from the beginning?

rixthetrick
Is it plausible that recordings that are captured through a broader frequency range (than considered hearing range), requiring a higher sample rate could bring digital closer to or even as good as analogue?
Sure, it's plausible. Why not listen to some hi-res digital and decide for yourself? Qobuz might be a good place for you to start.
Inadequate sample rate, yes. But oversight? Probably more like just your everyday engineering/marketing tradeoff. Happens all the time.

What I find interesting is when I reported here that my deaf from birth Aunt Bessie could "hear" music it was met with derision and insults. From the Hateful 18 granted, but still. So it was interesting to see in this paper:

"In a paper published in Science, Lenhardt et al. report that "bone-conducted ultrasonic hearing has been found capable of supporting frequency discrimination and speech detection in normal, older hearing-impaired, and profoundly deaf human subjects."

So take that, H18!
Dear friends : The human been skin has thousands of nervous ends/terminations that are extremely sensible and detect anything. There are hundreds of it by square mm. and from here goes to our brain.

It’s not only the bones that can detect and are sensible to SPLs but as I posted: hair, skin and all our body and this is not anectdotal issue. All what our full body sense is the experiences on MUSIC/SPLs that are detected and that we live it always.

Here something on the bones:

https://pubmed.ncbi.nlm.nih.gov/16019175/


If we wanted something more elaborated then read this:


http://www.tinnitusjournal.com/articles/response-of-human-skull-to-boneconducted-sound-in-the-audiometricultrasonic-range.pdf

and you can take a look to the References at the end of the article.


R.