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

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lashto

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Geert

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no test files were provided for others to check. No follow up, no luck...

Test file was provided by @pma https://audiosciencereview.com/foru...5khz-signal-audible-or-not.41848/post-1483392.

he mentioned there was no control test (i.e. he can actually hear a missingF)

Where did he mention he could hear a missing fundamental (except for the issue with IMD). His final conclusion was "Then I switched to the 22-33-44kHz test tone and could only hear dead silence from the tweeter. Even when I held my ear very close to the tweeter, I couldn't hear any sound".

That conclusion was validated by @danadam in another test where also a test file was provided https://www.audiosciencereview.com/...5khz-signal-audible-or-not.41848/post-1494601.
 

Julf

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Where did he mention he could hear a missing fundamental (except for the issue with IMD). His final conclusion was "Then I switched to the 22-33-44kHz test tone and could only hear dead silence from the tweeter. Even when I held my ear very close to the tweeter, I couldn't hear any sound".
I think @lashto meant to write "can he actually hear" instead of "he can actually hear", as @lashto is insisting on first verifying the person is capable of hearing a missing fundamental with harmonics at audible frequencies (as not everyone seems to be able to hear a missing fundamental).
 

Julf

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already upvoted that test quite a while ago and asked for details: he mentioned there was no control test (i.e. he can actually hear a missingF) and no test files were provided for others to check. No follow up, no luck...
We have realized that we won't have any luck getting you to admit you lost the bet, as you will always come up with something...
 

GXAlan

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that is a pretty strong test. Maybe it's not audible after all, although @GXAlan seems able to ABX 'something'.

1) IMD not at the missing fundamental from electronics and headphones

2) potentially some DC effect that would not be on a silent audio track that changes a pop. I should have done white noise at -120 dB instead.
 

ctrl

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already upvoted that test quite a while ago and asked for details: he mentioned there was no control test (i.e. he can actually hear a missingF) and no test files were provided for others to check. No follow up, no luck...

Sorry missed that. Will answer your questions below:

A few questions/comments:
  • the SB21RDC tweeter seems be linear up to ~30kHz only. Not very clear from the specs if the 44kHz will be played. A 9kHz test (i.e. HDs at 18-27-36kHz) would be fine for me too, don't think that any of us can actually hear 18kHz.
  • have you done the control test to check if you can actually hear/feel a missingF with audible HDs?

I checked some of the linked youtube videos and I can confirm that I could hear the "missing fundamental" in these examples, as others have already described, slightly distorted - checked!

According to the manufacturer's measurement, the tweeter hardly loses any sound pressure level up to 40 kHz. I can't check this exactly, since my microphone is only calibrated up to 20kHz.
1677085619137.png
The tweeter definitely transmits sound well above 40kHz, I can definitely measure that. It can only be that my microphone capsule itself already drops in frequency response in this frequency range.

To be sure, I repeated the complete test again (I hope you appreciate that, it's quite an effort, I did it just for you ;)), increasing the 44kHz tone by 15dB to compensate for a possible frequency response drop of the tweeter. In the third image you can see the difference of the 22-33-44kHz test tone with boost (orange) and without (green). It boosts the other test tones too slightly because of filter Q an the drastic 15dB SPL increase around 44kHz.

As always, all measurements were recorded with a microphone, so it is guaranteed that the tweeter really reproduced the tones.

Please keep in mind: The 44kHz tone still looks heavily attenuated (after the boost) in the measurement, but this is most likely largely due to the frequency response drop of the measurement microphone.

The first image shows the 11kHz reference tone which I could hear without problems.
The second image shows the 22-33-44kHz test tone with 44kHz 15dB boost, where I could only hear dead silence. The result is identical to the first test in post#74.

1677086589452.png 1677086612010.png 1677086633083.png

If you still have doubts, you should repeat the experiment yourself. This might not be a bad idea, so that you get an impression of how high 11kHz is and how difficult it is to hear such a test tone. A small head movement and you create a cancellation of the sound.
 

fpitas

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Playing devil's advocate here. Conceivably, someone's ears could be really non-linear and create the 11kHz tone.

/But it's unlikely
//Remind me why we care?
 

Cars-N-Cans

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If you still have doubts, you should repeat the experiment yourself. This might not be a bad idea, so that you get an impression of how high 11kHz is and how difficult it is to hear such a test tone. A small head movement and you create a cancellation of the sound.
Yeah I think people underestimate just how shrill frequencies get above about 10 kHz since the pitch gets progressively more compressed with increasing frequency. Its not linear at all. For all intents and purposes there's not much content above about 12 kHz in music. I think for the OP it would be instructive to use a PEQ with a LP filter and move the skirt progressively lower while listening to music. I suspect he probably wont hear much difference until the f3dB gets below about 10-11 kHz.
 

GXAlan

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Yeah I think people underestimate just how shrill frequencies get above about 10 kHz since the pitch gets progressively more compressed with increasing frequency. Its not linear at all. For all intents and purposes there's not much content above about 12 kHz in music. I think for the OP it would be instructive to use a PEQ with a LP filter and move the skirt progressively lower while listening to music. I suspect he probably wont hear much difference until the f3dB gets below about 10-11 kHz.

I have one of those JBL UT-405’s with -18dB/octave with a steep slope.

Even in the 24 kHz crossover, there’s plenty of musical content you can hear running these super tweeters and nothing else, even at normal listening levels. (65 dB with real music).

Doesn’t change that there is no “missing fundamental” effect from ultrasonics :)
 

Blumlein 88

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Yeah I think people underestimate just how shrill frequencies get above about 10 kHz since the pitch gets progressively more compressed with increasing frequency. Its not linear at all. For all intents and purposes there's not much content above about 12 kHz in music. I think for the OP it would be instructive to use a PEQ with a LP filter and move the skirt progressively lower while listening to music. I suspect he probably wont hear much difference until the f3dB gets below about 10-11 kHz.
Another thing I've done, do a steep filter at 20 khz, then slow down the speed of the file so that highest frequencies fall down to 10 khz and below. There is not much at all up there.
 
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lashto

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Looks like someone has actually done a very similar study to this... on bats. https://www.researchgate.net/figure...damentals-in-the-low-middle-and_fig4_13680570
very nice find, many thx.
Although the paper is about testing missingF in bats, it opened quite a network of related studies which seem to be quite relevant. It'll take me a while to process all that stuff.

Generally, it looks like there is even more research that I though related to the missingF phenomenon. Probably because it is very closely related to the perception of pitch. Which is actually quite far from being clear, a more recent meta-study ends up with:
In any case, the quest for a unified theory of pitch perception continues.
That seems to contradict some of the "expert" opinions in this thread.
Researchers from 10+ universities/institutes are looking very hard into the matter. And they consider "missingF at very high freqs" tests so worthy that they went through the trouble of training bats/cats/etc. But some of our know-it-alls are very sure that the whole question is a waste of time. Hope you'll 'forgive' me for not agreeing with that...
 
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Julf

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That seems to contradict some of the "expert" opinions in this thread. Researchers from 10+ universities/institutes are looking into the matter and even consider it worthy to study the missingF in bats/cats/etc. But some of our know-it-alls are very sure that the whole question a waste of time. Hope you'll 'forgive' me for not agreeing with that...
Nice try, but distorting facts pretty badly. We are not dismissing the missing fundamental - we are dismissing the supposed audibility of a missing fundamental if all the harmonics are beyond human hearing. Please don't try to obscure the issue even further in order to cover your failure.
 
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lashto

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hope it is also understandable that it's ~impossible to keep up with the pace of this thread. A lot more input that expected and I have a lot less available time than expected.

Right now I am trying to chase kemmler's bats :).
Haven't found any "final answer" but it looks like we can settle one major open question in the OP/bet: how many Hs are needed to test/hear a missingF effect?

(might be able to post that answer today)
 
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Geert

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That seems to contradict some of the "expert" opinions in this thread. Researchers from 10+ universities/institutes are looking into the matter and even consider it worthy to study the missingF in bats/cats/etc. But some of our know-it-alls are very sure that the whole question a waste of time

Lets revert to insults, very nice. You're moving the goal post. The question (title of the thread) is "Missing fundamental for a 15kHz signal - audible or not?". That question has been answered, which required a lot of effort from multiple people (involving real experts actually).
 
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lashto

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Lets revert to insults, very nice. You're moving the goal post. The question (title of the thread) is "Missing fundamental for a 15kHz signal - audible or not?". That question has been answered, which required a lot of effort from multiple people (involving real experts actually).
not sure how it's an "insult" to tell people they were wrong. Argumented. With study quotes even.
You/others tell me that all the time in this thread ... often with zero arguments. And I didn't start crying "mommy, mommy, some guy on the internet doesn't approve of my arguments" :)

Anyway, I surely could've missed something, feel free to point it.
At the same time, everyone is still missing the answer to the above Q. A bit 'afraid' already that the answer will not be very popular ...
 

Julf

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not sure how it's an "insult" to tell people they were wrong.

Are you being disingenuous or just dense? The insult was putting "experts" in quotes, not telling people that you think they are wrong.
At the same time, everyone is still missing the answer to the above Q. A bit 'afraid' already that the answer will not be very popular ...
No, the answer is clear and has been provided multiple times. The only one missing it is you.
 

Julf

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hope it is also understandable that it's ~impossible to keep up with the pace of this thread.
Really? It seems it is very easy for you, as you just ignore anything that disagrees with your speculation.
 
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lashto

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Really? It seems it is very easy for you, as you just ignore anything that disagrees with your speculation.
guess we have diff views about how this bet/thread is supposed to work.

I am only holding one side of the bet: the "it's audible" one. I/someone is supposed to act as an advocate for that side. Anyone else who wants that role is welcome. But I am not necessarily asking for that kind of help

You @Julf are holding the other side of the bet. And ~everyone else is supposed to do the same. Very highly welcome to!
No complaints there, many/most are doing a great job (much better than expected too).

Just let me do my 'job'. I haven't (blindly) refused anyone's argument, many of them are very much and very high "on the table".

P.S.
There is also quite a bit of talk about "beliefs". Sorry, none here.
It's a well described hypothesis, hopefully testable. I am asking for help to test/prove/disprove it.
I do not have high hopes for it and it's clearly somewhat feeble and fringe. But as long as there is no 100%-against proof, it'll stay (at least for me).
 
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Julf

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guess we have diff views about how this bet/thread is supposed to work.
Clearly, yes.
I am only holding one side of the bet: the "it's audible" one. I/someone is supposed to act as an advocate for that side. Anyone else who wants that role is welcome. But I am not necessarily asking for that kind of help
Yes, and you haven't provided any evidence at all.
You Julf are holding the other side of the bet.
No, i am not. Not any more. The bet is over, and you lost. Pay up.
It's a well described hypothesis, hopefully testable. I am asking for help to test/confirm/disprove it.
Have you actually read what people have been posting here?
I do not have high hopes for it and it's clearly somewhat feeble and fringe. But as long as there is no 100%-against proof, it'll stay (at least for me).
Problem is that you don't seem to accept any proof as "100%".
 
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lashto

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No, i am not. Not any more.
a bit amazed that your "offer" lasted that long. Not entirely my decision but from my side, feel free to leave the bet & the thread!
The bet is over, and you lost. Pay up.
Pretty sure that you cannot both leave the bet and demand payment at the same time :)
Have you actually read what people have been posting here?

Problem is that you don't seem to accept any proof as "100%".
The OP states what will be accepted as 100% proof. No freedom-of-choice for me or anyone else.
Anyway, already said that I cannot and did not keep up with the thread pace. Could very well be that there is a 100% up there. Judging by the answer to the "how many Hs" question, it cannot really be.
But I'll have to read a lot and many need to wait. Sorry...

P.S.
hope there won't be many other "arguments" like above. This stuff is useless for the test/bet and can only close the thread. Which is the last thing I want
 
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