2. analog
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'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
elliottbnewcombjr OP
5,330 posts
 
raul

ok, we will remain happily wrong.

I agree, the volume level may not be flat, but I am thinking about the TIMING of the fundamentals and overtones of each and every instrument’s sound waves, to their individual fundamental, and all the surrounding notes; even overtones we are unaware of, being ’right’ or ’wrong’ to our brain’s perception. Capturing and re-generating fundamentals and overtones ’right’.

I’m no scientist, but I play Sgt. Peppers, CD, LP, R2R, and EVERYONE who hears them on my system pick LP over CD and R2R over LP. Next, I switch from McIntosh MC2250 SS to Tube Amp, EVERYONE picks tubes. Same thing with any content I have in all 3 formats. I can switch SS/Tubes without them knowing what’s what

It's not clarity, lack of noise, because LP is noisier than CD and Tape is noisier than LP.

It’s not ’warmth’, not ’happy distortion’, what is it? You have my best guess, imperceivably perceived timing.


Ag insider logo xs@2x
rauliruegas
13,049 posts
 
Dear friends : For several years now I posted more than one time that human been can listen beyond 50khz and down beyond 20hz because we listen/hear through all our body: hair, bones, skin, etc, etc.

Even I posted that we have to have the experience to confirm it and for that we need to listen for at least one hour MUSIC tracks very well know for us seated in NAKED fashion ( only a boxer down there. ) at different controled SPL and inmediatly to that naked session listen same recordings with our normal clothes.
This experience is really a learning one and this link says that we really can listen with a more wide frequency range that we can imagine:

https://pdfs.semanticscholar.org/e6ed/9ec45208be612a60411e3b527d65b22962d0.pdf

So, GO NAKED !!  . You have to try it.

R.
elliottbnewcombjr OP
5,330 posts
 
movement of instrument/mouth, air, microphone, cutting stylus, moving magnetic material on tape, captured/played back by movement

the ’timing’ is ’not quite right’ when you add the step of direct conversion of movement or conversion of captured movement to digits, numbers, good numbers, more numbers, a heck of a lotta more numbers, then read and convert those whole lotta numbers back to movement.

what the heck is loz rez, high rez, super high rez all about?
teo_audio
2,197 posts
 
between two ears alone, on the exact same pulsed signal, the ears, as a pair, have a discernment level that goes well beyond 100khz, with regard to timing resolution, in stereoscopic placement of a ghost stereo signal. (it’s all reproduction and fakery)

and, in that, it must occur at the exact correct microsecond and at the exact correct level, with respect to the two signals coming out of the speaker pair.

to do so, requires an approximate 250khz plus sampling rate, and zero jitter of any kind. at a signal bit depth of at least 20 bits.

currently, we are incapable of recreating/building this. (Jitter)

never mind the sound of an orchestra in the same set-up.

there is additionally other fundamental problems with digital and BJT and Fet transistors.

V-Fet and SIT transistors are the only ones that are useful for human hearing discernment, when it comes to peak functions, and then there is tubes, which are also correct in the critical to human areas of signal reproduction. Analog tape and LP are also correct. Doug sax’s mastering system, BTW, was all tube. For this reason.

when digital was conceived and brought into the world, none of this was known or considered. Digital did some of the most critical (to human hearing) things wrong.... as it was, for the most part.. engineered--- not heard. Big mistake.
elliottbnewcombjr OP
5,330 posts
 
I found the 'hangover' effect interesting (3rd paragraph).

X. Significance of the results


Given the existence of musical-instrument energy above 20 kilohertz, it is natural to ask whether the energy matters to human perception or music recording. The common view is that energy above 20 kHz does not matter, but AES preprint 3207 by Oohashi et al. claims that reproduced sound above 26 kHz "induces activation of alpha-EEG (electroencephalogram) rhythms that persist in the absence of high frequency stimulation, and can affect perception of sound quality." [4]


      Oohashi and his colleagues recorded gamelan to a bandwidth of 60 kHz, and played back the recording to listeners through a speaker system with an extra tweeter for the range above 26 kHz. This tweeter was driven by its own amplifier, and the 26 kHz electronic crossover before the amplifier used steep filters. The experimenters found that the listeners' EEGs and their subjective ratings of the sound quality were affected by whether this "ultra-tweeter" was on or off, even though the listeners explicitly denied that the reproduced sound was affected by the ultra-tweeter, and also denied, when presented with the ultrasonics alone, that any sound at all was being played.

      From the fact that changes in subjects' EEGs "persist in the absence of high frequency stimulation," Oohashi and his colleagues infer that in audio comparisons, a substantial silent period is required between successive samples to avoid the second evaluation's being corrupted by "hangover" of reaction to the first.

...............................

me: what's a 'substantial time period'? silent for how long??? 

btw, I find many people can not even stop talking for the length of 1 song.

.......................................


      The preprint gives photos of EEG results for only three of sixteen subjects. I hope that more will be published.

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." [5] They speculate that the saccule may be involved, this being "an otolithic organ that responds to acceleration and gravity and may be responsible for transduction of sound after destruction of the cochlea," and they further point out that the saccule has neural cross-connections with the cochlea. [6]

Even if we assume that air-conducted ultrasound does not affect direct perception of live sound, it might still affect us indirectly through interfering with the recording process. Every recording engineer knows that speech sibilants (Figure 10), jangling key rings (Figure 15), and muted trumpets (Figures 1 to 3) can expose problems in recording equipment. If the problems come from energy below 20 kHz, then the recording engineer simply needs better equipment. But if the problems prove to come from the energy beyond 20 kHz, then what's needed is either filtering, which is difficult to carry out without sonically harmful side effects; or wider bandwidth in the entire recording chain, including the storage medium; or a combination of the two.
      On the other hand, if the assumption of the previous paragraph be wrong — if it is determined that sound components beyond 20 kHz do matter to human musical perception and pleasure — then for highest fidelity, the option of filtering would have to be rejected, and recording chains and storage media of wider bandwidth would be needed.


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