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Missing fundamental for a 15kHz signal - audible or not?

Geert

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I am not asking for anything new/special here

Of course not. Anyone with a 60Khz tweeter and a 60kHz microphone can do it. Or make it 75kHz (5th harmonic) to be sure. That's nothing extraordinary these days.

just the usual AES-paper-quality answer/test

I'll ask my colleagues if anyone's interested to work 3 months for 50€.
 
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Blumlein 88

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the direct and reproducible/verifiable test that I asked for :)

Done in the usual "nobody needs to trust anybody" manner.
If somebody says "I hear it", there should be no need to trust their words. They need to have clear/verifiable proof, e.g. the Foobar ABX with hashed 3rd party files.
Same goes for "I don't hear it". And (unfortunately) I have no idea how to make that statement provable. Help needed.

Otherwise, "I hear crickets" means nothing and "I don't hear crickets" means even less.

Yes, I could be the nice guy: just believe what anyone says and pay the bet. But that only 'proves' that I was nice and does not answer the question. Neither for me nor for anyone else.

P.S.
I am not asking for anything new/special here: it's just the usual AES-paper-quality answer/test requested on any other ASR thread.
This is about how I understood it. You wanted a thorough test of something no one bothers with because it has no chance of working, plus it is potentially dangerous to gear.

I see it like saying, " I wonder if eating one papaya a day prevents all heart disease? No studies showing it doesn't, so until someone shows otherwise it could be true." I hate analogy.
 

ctrl

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That is a bit too much digressing, back to the main Q. The short(ish) answers are:
  • 2 Hs are not enough to prove anything.
  • 3 Hs could be enough to prove a positive (i.e. it's audible). But not even close to enough for "not audible".
  • The whole "dominance region for pitch" (i.e. 4-5 harmonics) is used as the utmost minimum by pretty much everyone and every missingF study. Even for studies involving easily audible Hs/missingFs. For a "not audible" conclusion we need (at the very least) the same "utmost minimum".
3 Hs don't seem that great either, particularly for the "not audible" proof. I did not find a clear "you must have xx Hs" statement but 'everything' seems to point to "4-5 or more"

Okay, now you say that untrained listeners can reconstruct the missing fundamentally in the brain only from four, trained from three harmonics.

I assume that the bet (audibility of "missing fundamental" with 15kHz fundamental) was about real existing headphones and loudspeakers, through which one should be able to hear the missing fundamental.
If you insist on at least four harmonics (30kHz, 45kHz, 60kHz and 75kHz), then you have already lost the bet, since there are very likely no speakers or headphones that still reproduce 75kHz with full SPL.



But fine, you insist on at least four harmonics, then we'll do the whole test again. And to make it especially easy to hear the missing fundamentals, I use 8kHz as the fundamental.

First, Octave is used to generate the corresponding sine tones. The fundamental at 8kHz and the 16kHz, 24kHz, 32kHz and 40kHz harmonics.
We also have the sum of all sine tones and the sum of all harmonics (missing fundamental) generated graphically:
1677278124863.png

Graphically, omitting the fundamental seems to make little difference, there are still peaks with the spacing of the fundamental.
Octave now generates once the sum of all tones (A) including the fundamental and once only the sum of the overtones (B).



To check that everything was generated the way we wanted it, five second long wav samples are compared in DeltaWave:
1677278347617.png

The white curve corresponds to B and the blue curve to A, i.e. with the fundamental at 8kHz. The sample files are perfect.
The sample files to reproduce the experiment are attached.


The test setup was, as usual, a tweeter capable of transmitting the full sound pressure level up to over 40kHz and a microphone to check that all sine tones are really transmitted as planned.
1677278722516.png
1677279373364.png


The measurements confirm that all frequencies are transmitted. If only the harmonics are measured, the measurements show that the 8kHz fundamental is reproduced with -40dB attenuation (the cause is not quite clear to me, but would facilitate the hearing of the fundamental, so no problem).

Above 30kHz the SPL of the measured sinusoidal tones drops slightly, the reason for this is most likely the mic.
In yellow is the measurement of all sine tones (A) and in green is the measurement without the fundamental (B).
1677279037066.png


I then played the test tones with the 8kHz fundamental (A) so loud that it was barely tolerable.

Then I played the sine tones without the fundamental (B) without changing any setting. There was dead silence, even when my ear moved dangerously close to the tweeter (sometimes thought I could perceive the 16kHz tone).

After all the tests, I would conclude that @lashto clearly lost the bet. Even at 8kHz, the missing fundamental is no longer perceptible.
 

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tmtomh

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Okay, now you say that untrained listeners can reconstruct the missing fundamentally in the brain only from four, trained from three harmonics.

I assume that the bet was about real existing headphones and loudspeakers, through which one should be able to hear the missing fundamentals.
If you insist on at least four harmonics, then you have already lost the bet, since there are very likely no speakers or headphones that still reproduce 75kHz with full SPL.



But fine, you insist on at least four harmonics, then we'll do the whole test again. And to make it especially easy to hear the missing fundamentals, I use 8kHz as the fundamental.

First, Octave is used to generate the corresponding sine tones. The fundamental at 8kHz and the 16kHz, 24kHz, 32kHz and 40kHz harmonics.
We also have the sum of all sine tones and the sum of all harmonics (missing fundamental) generated graphically:
View attachment 267217
Graphically, omitting the fundamental seems to make little difference, there are still peaks with the spacing of the fundamental.
Octave now generates once the sum of all tones (A) including the fundamental and once only the sum of the overtones (B).



To check that everything was generated the way we wanted it, five second long wav samples are compared in DeltaWave:
View attachment 267218
The white curve corresponds to B and the blue curve to A, i.e. with the fundamental at 8kHz. The sample files are perfect.
The sample files to reproduce the experiment are attached.


The test setup was, as usual, a tweeter capable of transmitting the full sound pressure level up to over 40kHz and a microphone to check that all sine tones are really transmitted as planned.
View attachment 267219 View attachment 267228


The measurements confirm that all frequencies are transmitted. If only the harmonics are measured, the measurements show that the 8kHz fundamental is reproduced with -40dB attenuation (the cause is not quite clear to me, but would facilitate the hearing of the fundamental, so no problem).

Above 30kHz the SPL of the measured sinusoidal tones drops slightly, the reason for this is most likely the mic.
In yellow is the measurement of all sine tones (A) and in green is the measurement without the fundamental (B).
View attachment 267222

I then played the test tones with the 8kHz fundamental (A) so loud that it was barely tolerable.

Then I played the sine tones without the fundamental (B) without changing any setting. There was dead silence, even when my ear moved dangerously close to the tweeter (sometimes thought I could perceive the 16kHz tone).

After all the tests, I would conclude that @lashto clearly lost the bet. Even at 8kHz, the missing fundamental is no longer perceptible.

Nicely done - thanks!
 

antcollinet

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Okay, now you say that untrained listeners can reconstruct the missing fundamentally in the brain only from four, trained from three harmonics.

I assume that the bet was about real existing headphones and loudspeakers, through which one should be able to hear the missing fundamentals.
If you insist on at least four harmonics, then you have already lost the bet, since there are very likely no speakers or headphones that still reproduce 75kHz with full SPL.



But fine, you insist on at least four harmonics, then we'll do the whole test again. And to make it especially easy to hear the missing fundamentals, I use 8kHz as the fundamental.

First, Octave is used to generate the corresponding sine tones. The fundamental at 8kHz and the 16kHz, 24kHz, 32kHz and 40kHz harmonics.
We also have the sum of all sine tones and the sum of all harmonics (missing fundamental) generated graphically:
View attachment 267217
Graphically, omitting the fundamental seems to make little difference, there are still peaks with the spacing of the fundamental.
Octave now generates once the sum of all tones (A) including the fundamental and once only the sum of the overtones (B).



To check that everything was generated the way we wanted it, five second long wav samples are compared in DeltaWave:
View attachment 267218
The white curve corresponds to B and the blue curve to A, i.e. with the fundamental at 8kHz. The sample files are perfect.
The sample files to reproduce the experiment are attached.


The test setup was, as usual, a tweeter capable of transmitting the full sound pressure level up to over 40kHz and a microphone to check that all sine tones are really transmitted as planned.
View attachment 267219 View attachment 267228


The measurements confirm that all frequencies are transmitted. If only the harmonics are measured, the measurements show that the 8kHz fundamental is reproduced with -40dB attenuation (the cause is not quite clear to me, but would facilitate the hearing of the fundamental, so no problem).

Above 30kHz the SPL of the measured sinusoidal tones drops slightly, the reason for this is most likely the mic.
In yellow is the measurement of all sine tones (A) and in green is the measurement without the fundamental (B).
View attachment 267222

I then played the test tones with the 8kHz fundamental (A) so loud that it was barely tolerable.

Then I played the sine tones without the fundamental (B) without changing any setting. There was dead silence, even when my ear moved dangerously close to the tweeter (sometimes thought I could perceive the 16kHz tone).

After all the tests, I would conclude that @lashto clearly lost the bet. Even at 8kHz, the missing fundamental is no longer perceptible.
Holy hell, that is troll baiting raised to fine art. Chapeau!
 

Cars-N-Cans

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After all the tests, I would conclude that @lashto clearly lost the bet. Even at 8kHz, the missing fundamental is no longer perceptible.
And the biting irony is that he actually posted a link to a paper that showed house cats that have hearing that is purported to extend up to a staggering 85 kHz cannot hear the missing fundamental above about 6 kHz. The only reason humans can potentially hear them up to almost that frequency is due to their more complex auditory system.

In terms of the original bet, even when your own papers you quote prove you are wrong, I think you lost conclusively:)
 

Geert

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And the bat test he loves so much; all the fundamental frequencies they used were easily in the audible frequency range for bats. For people, even the first harmonic of 15kHz is way beyond the audible range. For the last test @ctrl did (8kHz fundamental) the first harmonic is on the edge of audible, but the higher one's are not.
 

HarmonicTHD

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And the biting irony is that he actually posted a link to a paper that showed house cats that have hearing that is purported to extend up to a staggering 85 kHz cannot hear the missing fundamental above about 6 kHz. The only reason humans can potentially hear them up to almost that frequency is due to their more complex auditory system.

In terms of the original bet, even when your own papers you quote prove you are wrong, I think you lost conclusively:)
Yep. And mark my words… the troll will be back in no time claiming the opposite and waiting to be fed again.
 

solderdude

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I offered to donate €50 to ASR if someone does a (credible) test. And increase that to €100 is someone figures out an easy test that can be done by AverageAsrJoe. Or even by me (details in the spoiler below).

Time to admit defeat and pay up (or make a donation to ASR). Some have gone beyond the call of duty and the tests done were credible so....
You may have wanted to get a confirmation of your theorizing but that (as expected) did not happen. Doesn't make the efforts done by a few ASR members not credible.

Of course post #5 already touched the essence of the whole 'missing fundamental' part.
Just like post #160 did by the way.
 
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Cars-N-Cans

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For that matter even the premise of the test doesn't even really make sense. He stated in post #211:

That is a bit too much digressing, back to the main Q. The short(ish) answers are:
  • 2 Hs are not enough to prove anything.
  • 3 Hs could be enough to prove a positive (i.e. it's audible). But not even close to enough for "not audible".
  • The whole "dominance region for pitch" (i.e. 4-5 harmonics) is used as the utmost minimum by pretty much everyone and every missingF study. Even for studies involving easily audible Hs/missingFs. For a "not audible" conclusion we need (at the very least) the same "utmost minimum".

Having the missing fundamental so high pretty much ignores the fact that the ear likely covers the range of frequencies it does, i.e. 20Hz - 20kHz, so its response can be at least somewhat uniform and flat in the region of interest from about 40Hz - 10kHz. Having it go a bit higher is not so you can hear forever! Its to ensure there isn't an undue roll-off of the ear's response in the normal range of hearing. Above about 14kHz, tones don't even really make sense musically to me, anymore. They are just obnoxious, unwanted, shrill noises. And yet we need to be able to hear multiples of this just to make out the missing fundamental.
 

Andysu

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Alien 3 six track Dolby Stereo THX sound system JBL hf up 18,000KHz no problem 15KHz


when it comes to hf high fidelity high frequencies the JBL THX sound system deliverers it with startling realism
picture of previous JBL control 12SR modified , Sooty even approved of it . the newer JBL is five screen wide JBL 4673A and Sooty even approves of that
alien3hf2.jpg
 
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Blumlein 88

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How can you watch anything after Alien in that movie franchise?
 

antcollinet

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How can you watch anything after Alien in that movie franchise?
Alien was excellent - but Aliens was better. The one after that was the worst. The one after that one - that was the worst too. After that it went into a bit of a decline.
 

fpitas

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Hi

I suggest that the OP , pay at least treble :D
which would be most appropriate for having taken people on a fool's errand.
:p

Peace
With all that ultrasonics, there will be treble damages.
 

fpitas

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Never more appropriate:

duty_calls.png
 

tomtoo

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No, they are not. If your speculation is true, you should be able to hear a 11 kHz missing fundamental even with just a 22 kHz harmonic.

Indeed.

I cant hear the harmonic but i can hear the missing fundamentel from it? Thats a wild theory.
 

Julf

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I cant hear the harmonic but i can hear the missing fundamentel from it? Thats a wild theory.

Indeed. Leading to a wild-goose chase.
 

Cbdb2

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Whats a missing fundamental? How does our brain know its missing. If we remove the fundamental from a bass guitar by playing a regular guitar why does it not sound like a bass? If our brains fill in the low freq fundamental why do we need subs? Do you hear a difference when you use a sharp highpass on a single note of a bass to get rid of the fundamental? Why don't we hear sub harmonics on all instruments that have there fundamental, again, how does our brain know if the fundamental is there or not?
 
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