[SilverEars]

On one of the threads, I ran into this product from japan for an iem.  It has dots in the canal of the tip and described as below(google translation).  What's the benefit of it what would it do to the sound?  I looked up something similar online, and all I see is diffusers for room treatment.  Any parallel to that?
 

It comes with the newly developed "spiral dot earpiece" to achieve a clear sound

It comes to suppress the turbidity of the sound is diffused in the dimples provided in the earpiece inner wall the reflected sound of the earpiece that is the cause of the deterioration in sound quality, to achieve a clear sound the "spiral dot earpiece". Foam earpiece to fit in the ear with a soft touch is also included.

Foam earpiece is ※ service parts handling. (S, M each 2 pcs.) Contact: Customer Support Center
 

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Silicon earpiece

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Earpiece sectional view

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[cswann1]

I'm not any kind of engineer, but when I read the above and try to imagine what it is they are trying to accomplish I think of a flashlight.
 
Ideally you want a nice smooth, even circle of light.  There are a few tricks that are used to get this. One of them is a textured reflector.  These don't have a smooth, flat surface. The surface of the reflector is textured so that the light reflected is smooth and even and doesn't have any darker or lighter areas.
 
 
I honestly don't know if sound pressure waves act light light to any degree or whether introducing these smoothing dimples has any positive effect on sound.   If I were to guess I'd say that this is likely just a gimmick and you could spend years A-B testing tips with and without these dimples and never come to any useful conclusions.
    If you like the sound and comfort of the IEM and the price fits....get em and don't give the dimples a second thought.

 

[proton007]

Firstly, sound waves are longitudinal, different from the transverse nature of light.
 
Secondly, I'm not too convinced by the 'turbidity' argument. How does sound exhibit turbidity? How does that affect sound quality, and how do the dots change this for better?
Until these questions are answered, I'll say it's just some pseudo-technical jargon.

 

[ab initio]

  Firstly, sound waves are longitudinal, different from the transverse nature of light.
 
Secondly, I'm not too convinced by the 'turbidity' argument. How does sound exhibit turbidity? How does that affect sound quality, and how do the dots change this for better?
Until these questions are answered, I'll say it's just some pseudo-technical jargon.

Turbidity is an incorrect word in this context. It makes no sense. One can speculate what the author thought they were saying.
 
As for the dimples, they can't really do anything at all. If you check the wavelength of sound in the audible range then you will notice that even the highest frequencies have wavelengths many times the size of those dimples; therefore, those dimples are too small to interact with the sound waves in any appreciable way.
 
If you consider the "air flow" past these dimples due to 120 dB SPL sound (instant ear damage), then the velocity of the air displacing with the sound waves is 0.049 m/s. At typical atmospheric conditions, and assuming that the dimples are approximately 3mm or so in size, then the Reynolds number of the acoustically driven airflow is only 9. Hence, we can conclude that the air flowing back and forth past the dimples is laminar and that these dimples are a gimmick that cannot physically affect the sound.
 
Cheers
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