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Hearing Damage over 20khz?

I own speakers that produce in excess of 40khz, yet the human ear can only perceive 20khz.

If something is uncomfortably loud we can hear, we know to turn it down but what if the frequency is out of our audible range?

Is it possible hearing is being damaged by something we can't hear?

I have read reports of people having ears ring after using speakers that can go beyond 20k, but I don't know if it's due to the sounds produced below 20k or above or both.

It would be horrible to learn I was damaging my children's ears or mine without knowing it.
vintagegroove
eldartford
4,262 posts
 
Shadorne... And there are woofer hairs, midrange hairs, and tweeter hairs. However, the ON/OFF mechanization can represent waveform as well as frequency.

What is your explanation of ability to sense the existance or absence of frequencies higher than measured sine wave sensitivity?
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shadorne
7,477 posts
 
What is your explanation of ability to sense the existance or absence of frequencies higher than measured sine wave sensitivity?

Huh? Not sure I understand you. I don't think there is evidence that we hear higher frequencies.

A square wave is made up of all odd harmonics...you hear the odd harmonics up to the point where you can no longer hear them (around 15 KHz for most people)...so you do not hear the "slope" of the square wave but within your audible hearing range you hear the harmonic content that makes up the square wave.
eldartford
4,262 posts
 
Shadorne... I am very familiar with Fourier analysis. (I used it a lot in my role as a test design engineer).

Evidently you have not experienced the phenomina which I described. The ongoing interest in supertweeters is further evidence that frequencies above the measured hearing range do matter.
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shadorne
7,477 posts
 
Yes there is some interest in frequencies higher than "audible" however it appears to be the non-linear properties of the air and the way differences between high frequency tones that can make audible sounds (beat tones).

Fundamentally what we hear is still within the audible range of frequencies and there is no evidence that we can actually hear pure tones well above 20 KHz.
eldartford
4,262 posts
 
Shadorne... Agreed... "there is no evidence that we can actually hear pure tones well above 20 KHz".

But we can detect the presence or absense of such tones. Perhaps this is because of beat frequencies as you suggest.

Listen to a 20KHz square wave and a 20 KHz sine wave. I bet you can tell them apart(if you can hear them at all. If not try a lower frequency). The only difference is the higher harmanics in the square wave.
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