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OT:The frequency range of musical instruments above 20khz

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

This is something I've found interesting and should of posted before, my mind has a habit of wondering tho. Came across an oldish research paper online measuring the frequency range of acoustic instruments, drums and other objects up to 102.4khz, which was the limit of some of the equipment used.

Speaking of which I looked up the equipment for this test, couldn't find the HP 3567A FFT spectrum analyzer, but I did find an HP 35670A online and its frequency response goes up to 102.4khz.

http://www.testequipmentdepot.com/usedequipment/hewlettpackard/spectrumanalyzers/35670a.htm

The microphones used were an 1/4 inch Acopacific 7016 which goes up to 120khz and a 1/4 inch Bruel & Kjaer 4135 which was rated at 4hz to 100khz. An 1/2 inch Acopacific 7012 was also used for collateral measurements, not quite sure what that means:)

http://acopacific.com/micdetal.html
https://www.bksv.com/media/doc/Bp0100.pdf

In the paper, it goes into detail about how different things could skew the results, like the room, objects in the room, microphone response curves, aliasing etc. Then goes into brief explanations how these things were overcome or adjusted for. Now onto the results, couple of things I found surprising were most instruments power fell under the 20khz range, with only slight energy above 20khz, apart from crash cymbals and keys jangling.

Crash cymbals in particular had 40% of there energy above 20khz and extended passed where the equipment could measure, above 102.4khz. Keys had 68% of there energy above 20khz, but topped out at around 60khz. Claves also went passed where the equipment could measure, but at much weaker power than cymbals.

So why post this if the human hearing range taps out around 20khz, which would mainly be for younger people with great hearing. Two reasons, first one of the most interesting parts of this for me which I'll quote below so I don't butcher it, is the fact that people do respond to ultrasonic sound, above 20khz and also infrasound below 20hz. So does this really matter if playback systems don't replicate this, erm, good question, shit I'm talking to myself again.

Well sounds in the environment don't have the restrictions of play back systems, so understanding the range of sounds, limits of hearing and response to things outside our range might be helpful in gaining a fuller understanding of sound and its affects on people.

Now onto the interesting quotes.

'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."

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.'

Second point, forget people for a minute as we are quite limited when it comes to hearing, or should I say optimised for voice and any animals that might eat us. We are surround by all sorts of animals and other critters who do have a much larger range, some of them might be fans of your music or squealing as the case maybe. Case in point cats have a range of between 45hz to 64khz and yes cats do like some music, there is even music specially made for cats.

http://www.musicforcats.com

But the champion when it comes to range is the porpoise, go mammals, this mofo hasn't even got visible ears, has a reputed range of 75hz to 150khz and will be able to hear the crash cymbal in all its glory.

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Comments

  • LADDER! But where's the HP sauce....

  • I had a cat who loved all sub genres of jazz (from Dixieland to free) and anything with Robert Quine's playing. He would come running into the room and lie in front of a speaker whenever any of these types were being played. He did not care for anything else. Nicky was a real cool cat; RIP.

  • I turned to google in the hopes of deciphering the mysterious message and ended up in a strange place. @knewspeak are you accusing my porpoise of being a sausage?

    @JeffChasteen Nicky had good taste and is now in jazz heaven with my cat blake 7, listening to live jazz, strange how cat was a compliment for jazz peeps to call each other, I wonder if they knew or had cats.

  • edited November 2016

    not just Jazz: it's used in 'Blue Suede Shoes' as well as in Bowie's Diamond Dogs...

  • Definitely interesting stuff. Thanks for sharing.

  • edited November 2016

    Why does this matter?
    Ok ultrasound or very low vibration can make you feel uncomfortable, but ...

    Harmonics, cough, sound the same in higher pitches, it all sounds like a sine, no matter if it's saw or pulse ... ;)
    Hearing higher frequencys is about if you can hear the annoying beep or not ;)

    So let's have some fun with frequencys we usually can't hear, let's record cymbals with a measurement mic and pitch it down,

    Let's look at low frequencies now,
    Nothing happening here except you want to simulate earthquakes or Charme snakes
    Also not very musical ;)

    hm, nothing unexpected happening here, move on folks ...

    48 kHz is really ok ;)

    BTW. Frequencies between 10 & 20 kHz looks like a big deal if you look at the numbers,
    But if you map it to the musical keyboard it's just one octave -
    (This is a much better point of reference, numbers always sound to impressive)
    So 40 kHz is only one octave up to what a baby is supposed to hear ;)

    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."

    Interesting, but not impressive
    If you don't understand what is going on
    If you close your eyes you also produce more alpha waves ...
    This also alters your perception
    "Perception of sound quality" is an interesting topic
    Perception is quite bendable because your brain is constantly throwing away information

  • I wonder why the piano is showing up in that list
    Must be the last few keys on the upper end that no one plays because they sound so bad :D

  • edited November 2016

    @lala said:
    Why does this matter?

    For music, I don't think it does. A good song works on wax cylinder or an answering machine tape.

    Still, I think it's interesting. Particularly that the Harmon muted trumpet when played 20db quieter produced more 400% more spectral energy above 20k (relative to itself).

    Main takeaway for me:

    Be kind to animals: record music at 32khz.

  • edited November 2016

    I think the brass is like the "s" ...
    It's a byproduct of how it's created?

    So let's make the most annoying music ever
    Triangle, brass, calves and crash cymbals
    And a singer that goes SSSSSSSSSSSSSS
    The band goes by the name high on frequencies
    :D

  • edited November 2016

    Hm
    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.

    Huh? After 2 seconds I have forgotten what I heard 3 seconds ago, you can't compare audio like that.
    You could play me two times the same thing after waiting 3 sec and I would tell you all kinds of bs

    I understand they need to do this because of the latency and echo (they are looking at eeg) but I am unsure what the results in perceived perception quality are supposed to be in this test scenario.

  • @lala said:
    I think the brass is like the "s" ...
    It's a byproduct of how it's created?

    So let's make the most annoying music ever
    Triangle, brass, calves and crash cymbals
    And a singer that goes SSSSSSSSSSSSSS
    The band goes by the name high on frequencies
    :D

    The first track should be called - High pass can't touch this, or Ain't got no need for EQ...LOL

  • edited November 2016

    Perception: let's do lip reading from a puppet


    (I have no idea why I can't embed this)

  • the 2nd link is from the 'mobile' part of the YT site - exchange the m by a www will cure it

  • edited November 2016

    Nope

  • @lala said:
    "Perception of sound quality" is an interesting topic
    Perception is quite bendable because your brain is constantly throwing away information

    This is one of the things that I find intriguing, can the subtle use of ultrasound and infrasound have an effect on the way people experience music. Another part of the paper that I found interesting was this bit.

    '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'.

    My thinking on this, which is something I've pondered over for a while, is, can we as creators, mixers, engineers, utilise infrasound and ultrasound, to create more immersive musical experiences in our recordings. At the moment that would be no as playback systems usually only extend to the optimised range of hearing.

    However when you go to listen to live music, without mic's or amplification etc, you get the full range and respond to that, could be an orchestra or your friends playing guitar, singing and using improvised percussion round a camp fire. Now I'm not saying just extend the range into ultrasound and leave it at that, that would be dumb and a wasted opportunity.

    You'd still de-es vocals, percussion and other elements in that range, still use lo-pass, hi-shelf filters and other tools to soothe the high end on annoying sounds like wild cymbals, do the things you usually do, but then just add subtle elements here and there, outside the conscious hearing range, excite different places in the ear to enhance the listenening experience.

    For example, maybe use something as simple as a sine wave in the ultrasound range, modulate it with an lfo or use a tremolo effect to simulate the vibration of a string instrument, making sure to have slightly different rates for different keys. Not trying to use this as something you consciously hear, more something you feel as a tiny vibration, that your brain can then have fun with interpreting. Then mix this in with a synthesized string sound following the same notes, to maybe trick the brain into thinking its a live recorded instrument.

    Or on the other end of the spectrum, using infrasound, subtly of course, you don't want to off balance your mix, suck up all the bandwidth and life out of it, just to give people brains the feeling of presence, like the music is wrapped around them. Again this is something you'd feel, however slight and not hear, technically that is, but your brain would interpret, especially if the rest of the music is giving it cues to follow, higher up in the spectrum.

    As music is vibrations your brain interprets anyway, why not utilise and explore what falls outside of our hearing range to enhance or indulge on the experience. I've read a little bit of research about noise pollution and the effects it has on people's moods, well being and hearing, with exposure to especially industrial machines, underground trains etc, that belt out ultrasound and infrasound having detrimental effects.

    So it would be nice if this was more understood, for animals too I hasten to add, minimised or eliminated altogether and focus put more on the positive, creative and healing sides of sound outside our range, which has already been happening, still a lot of ground to cover and understand tho, imo.

  • @syrupcore said:
    Definitely interesting stuff. Thanks for sharing.

    I come across interesting things to post on my travels then get sidetracked and forget about them, this was one that has been rattling around in my mind for a while, but haven't quite understood fully yet, so I wanted to see what everyone else thought, help me understand it better.

  • A video on youtube I thought was interesting, even though again this would be limited by the range of the speakers, amp, headphones etc.

  • edited November 2016

    @Telefunky said:
    not just Jazz: it's used in 'Blue Suede Shoes' as well as in Bowie's Diamond Dogs...

    What is also used in Bowie's Diamond Dogs?
    I ask because I really enjoy the whole robotic space age cabaret vibe production of the record.
    It also contains a wealth of Bowie's criminally underrated guitar playing.

  • edited November 2016

    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."

    Wait a minute. ultrasonic and support of speach detection, huh?
    Hm, that was an "s" ok,
    Bone conducted is uncomfortable in a tec setup,
    Tie a speaker to your chest or absurd levels?

    Frequency discrimination in ultrasound
    I have no idea what they are talking about
    They could tell this is a higher or lower frequency now?

    It's kind of hard to follow this if you don't have the complete article, I can only guess what they were doing.

    Perception of soundquality ...
    I don't think they are talking about the pleasures of music at all
    I think it's basic research about basic understanding of language (I don't understand what the person next to me is saying) ...

    Think hearing implants and not music.
    Music with hearing implants must sound like shit ...

  • edited November 2016

    @mister_rz said:
    A video on youtube I thought was interesting, even though again this would be limited by the range of the speakers, amp, headphones etc.

    Please not vinyl vs cd again
    I don't care about frequencys I can't hear ;)
    But I care about dynamics and stereo, vinyl is very bad at this.
    And vinyl sucks monkeys ass because the quality gets worse every time you play it back. And it introduces really bad artifacts, dust, rumble, crackling, sometimes there are really bits missing because the needle jumps over a scratch...
    The fist track on the lp is always the banger and the soft things are later on because the sound quality gets worse towards the end of the record ... vinyl is a really weird medium.
    And it sounds nothing like what you have recorded and sent to the vinyl people to press it ... that's why you get a test pressing before it goes into production ...

  • @JeffChasteen said:
    What is also used in Bowie's Diamond Dogs?
    I ask because I really enjoy the whole robotic space age cabaret vibe production of the record.

    verse 2: The Halloween Jack is a real cool cat - and lives on top of Manhattan Chase
    the elevator's broke, so he slides down a rope - out on the streets you go, go Tarzie go man go...
    I always liked the idea of rapelling down a skyscraper (as a rock climber myself)
    great record for shure B)

  • @Telefunky said:

    @JeffChasteen said:
    What is also used in Bowie's Diamond Dogs?
    I ask because I really enjoy the whole robotic space age cabaret vibe production of the record.

    verse 2: The Halloween Jack is a real cool cat - and lives on top of Manhattan Chase
    the elevator's broke, so he slides down a rope - out on the streets you go, go Tarzie go man go...
    I always liked the idea of rapelling down a skyscraper (as a rock climber myself)
    great record for shure B)

    Ah, Halloween Jack was indeed a real cool cat (and so many people just thought he was Ziggy with an eyepatch!)
    It really is a great record in a great body of work.

  • @lala said:

    Wait a minute. ultrasonic and support of speach detection, huh?

    >

    Yes, in the ultrasonic range, they tested this on people with normal hearing, older hearing impaired people and profoundly deaf people and got similar results. People could detect both frequencies and speech in the ultrasonic range through bone conduction hearing. From the abstract,

    'When speech signals were modulated into the ultrasonic range, listening to words resulted in the clear perception of the speech stimuli and not a sense of high-frequency vibration'.

    >

    Frequency discrimination in ultrasound
    I have no idea what they are talking about
    They could tell this is a higher or lower frequency now?

    Yes the brain would do its thing and translate the vibrations into something intelligible.

    It's kind of hard to follow this if you don't have the complete article, I can only guess what they were doing.

    I can only find the abstract online from the original source, if I dig a bit I'll probably find the full paper, they are basically testing people's ability to discern sound in the ultrasonic range using bone conduction of the skull and ear, found another full paper by the lead author, which is along similar lines, some very interesting things in it, haven't read it all yet tho, here's one juicy quote,

    'Although hearing by air conduction is limited to about 20 kHz, hearing by bone conduction extends to at least 100 kHz'

    >

    Perception of soundquality ...
    I don't think they are talking about the pleasures of music at all
    I think it's basic research about basic understanding of language (I don't understand what the person next to me is saying) ...

    I'm talking about music pleasure and hacking the brain to increase that pleasure, which is something we do anyway consciously or unconsciously when making music in an contained environment, like on an ipad, computer, studio etc, as opposed to an open environment, live, which doesn't have the same constraints.

    We use reverb, delay etc, to give a sense of space, m/s processing, phase inverting one or both channels, mixing that back in with the original source and all sort of different techniques to mimic how we hear sounds and give a sense of depth, width etc, make it seem like the music is bigger than the speaker or headphones.

    This all interests me as I never considered using the ultrasonic and infrasonic ranges, usually cut those things out, but now my mind is wondering how could this all be used, if at all, could you affect the perceived quality of a piece of music using these ranges subtly, can you protect people's hearing by adding clarity in the ultrasonic range and a touch of low energy in the infrasonic range, then drop the volume in the audible range.

    What the researchers were looking into was about perception of sound outside of the audible range and also bone conductivity of sound in general, more geared to treating tinnitus, hearing loss and total deafness, it's in its infancy at the moment, but I find it all exciting and need to learn more.

    Here was the original research published in science, it's only the abstract tho, but interesting never the less.

    http://science.sciencemag.org/content/253/5015/82

    Here is a more in depth look at another paper published by the same lead author with different collaborators, need to go through this one myself, but their are a few interesting things I've read so far.

    http://www.tinnitus.vcu.edu/Pages/Human Skull Response.PDF

  • @JeffChasteen said:

    @Telefunky said:

    @JeffChasteen said:
    What is also used in Bowie's Diamond Dogs?
    I ask because I really enjoy the whole robotic space age cabaret vibe production of the record.

    verse 2: The Halloween Jack is a real cool cat - and lives on top of Manhattan Chase
    the elevator's broke, so he slides down a rope - out on the streets you go, go Tarzie go man go...
    I always liked the idea of rapelling down a skyscraper (as a rock climber myself)
    great record for shure B)

    Ah, Halloween Jack was indeed a real cool cat (and so many people just thought he was Ziggy with an eyepatch!)
    It really is a great record in a great body of work.

    I'm wondering now whether this is all down to tabby mind control, plus I've got cool for cats stuck in my head, as pets go, cats usually have the most freedom and are one of the few animals that can demand food, without being the size of a bear.

    http://www.livescience.com/5556-cats-control-humans-study-finds.html

  • @mister_rz said:

    @lala said:

    Wait a minute. ultrasonic and support of speach detection, huh?

    >

    Yes, in the ultrasonic range, they tested this on people with normal hearing, older hearing impaired people and profoundly deaf people and got similar results. People could detect both frequencies and speech in the ultrasonic range through bone conduction hearing. From the abstract,

    b 'When speech signals were modulated into the ultrasonic range, listening to words resulted in the clear perception of the speech stimuli and not a sense of high-frequency vibration'.

    /b

    >

    Frequency discrimination in ultrasound
    I have no idea what they are talking about
    They could tell this is a higher or lower frequency now?

    Yes the brain would do its thing and translate the vibrations into something intelligible.

    It's kind of hard to follow this if you don't have the complete article, I can only guess what they were doing.

    I can only find the abstract online from the original source, if I dig a bit I'll probably find the full paper, they are basically testing people's ability to discern sound in the ultrasonic range using bone conduction of the skull and ear, found another full paper by the lead author, which is along similar lines, some very interesting things in it, haven't read it all yet tho, here's one juicy quote,

    'Although hearing by air conduction is limited to about 20 kHz, hearing by bone conduction extends to at least 100 kHz'

    >

    Perception of soundquality ...
    I don't think they are talking about the pleasures of music at all
    I think it's basic research about basic understanding of language (I don't understand what the person next to me is saying) ...

    I'm talking about music pleasure and hacking the brain to increase that pleasure ...

  • edited November 2016

    'When speech signals were modulated into the ultrasonic range, listening to words resulted in the clear perception of the speech stimuli and not a sense of high-frequency vibration'.

    Hm, if I read this the other way around it says this only works with speach,
    Music results in a sense of high frequency Vibration.
    This makes sense.
    Understanding speach gives you an evolutionary advantage,
    Music doesn't in that way, but maybe it gets you laid. (lol)
    Our brains are obsessed with understanding speach ...

  • very interesting observation - thanks for the hint B)

  • edited November 2016

    BTW. Noise pollution also works the other way round
    I like to listen to a hairdryer, modulated white noise, or ocean waves when I go to bed. (All of this is more or less the same sound) This isolates me from other noises, my idiot neighbors and street noises ...

  • @lala
    Find the sound of waves quite calming, love sampling them when I'm at beach, might try listening back to them when my neighbors decide to start a party at three in the morning. We're definitely wired for speech, from what I've read the brain will automatically translate anything it's familiar with in the ultrasound range, Im curious to see how it handles unfamiliar sounds too.

    Would also be interesting also seeing how the brain responds to a live orchestra, compared to a recording that doesn't include the ultrasound range, but is a high quality recording, using newer tech that gives more information than an EEG. Find the science of it all amazing, especially for people with hearing impairments, real break through tho will be when synthetic telepathy, moves from military and intelligence applications and is used for treatment and more positive things.

    I watched a documentary a while back about transhumanism and where the civilian science was at, found it very fascinating and slightly disturbing too. One of the parts that stood out was when they hooked a cat up to these clumsy looking sensors, that cat didn't look to happy about this, then played back a movie of random people, tapped into its visual cortex and projected it onto a second monitor.

    It seemed like the cat, in the original video I watched anyway, did something that we do, but instead of humanising what it saw, it turned people more feline, video below is grainy so it doesn't show up as well, kind of intriguing seeing how the brain translates what it see's into something familiar, like with sound.

  • edited November 2016

    To bad the video is so grainy
    But the guy really looks a little dog like

    I know it's horrible to see our beloved pets cut up like that
    But if we don't do this we will die dumb

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