A Few Questions About the Acoustic Reflex and Sound Waves

[IvanRus]

@Samir, @Aaron123, @Markku
Let me ask some theoretical questions about the physics of sound and physiology of the human ear.

1) Is it true that the loud sound that happened suddenly, unexpectedly for a person and did not even have time to prepare for this loud event, is more dangerous to the inner ear, such as the acoustic reflex in this case is slower, plus a fazer of fright is possible?
What do you think?

2) Is it true, by the way, I read somewhere that sounds of a higher frequency are more dangerous to the inner ear, since the acoustic reflex of our ear works primarily on low-frequency sounds, but works weaker at high frequencies.
What do you think?

Thank you

 

[GregCA]

1) Is it true that the loud sound that happened suddenly, unexpectedly for a person and did not even have time to prepare for this loud event, is more dangerous to the inner ear, such as the acoustic reflex in this case is slower, plus a fazer of fright is possible?
What do you think?

I did learn that the element of surprise affects the reaction of the muscles in the middle ear that will not dampen the movements of the ossicular chain as much as if the person was aware that a loud sound was going to occur.

2) Is it true, by the way, I read somewhere that sounds of a higher frequency are more dangerous to the inner ear, since the acoustic reflex of our ear works primarily on low-frequency sounds, but works weaker at high frequencies.

It would depend on power, right? any frequency band can be dangerous if enough power is pushed through it. In general, the sounds we are exposed to don't have that much energy in the high frequencies, so we aren't that exposed to high frequencies. Most pieces of equipment dealing with sound are now digital, and will compress sounds to save bandwidth, with a side-effect of ditching high frequencies (see Nyquist).

When we get old, the high frequencies are generally the first ones we're going to "naturally lose" (see presbycusis).

 

[dingaling]

Just to add to this... the hair cells most responsible to high frequencies are in the basal turn of the cochlea which is closer to the middle ear (and the outside) than the apical turn that is more sensitive to lower frequencies. Therefore the high frequency region of the cochlea "takes the hit" first