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I can understand the mechanism of frequency dependent sound absorption by most materials but does the sound attenuation also depend upon the amplitude (sound pressure or rather loudness/sound intensity)? I tried some googling but unfortunately could not find any reliable source but my self thinking and intuition tells me that the answer is yes, it does depend on amplitude of the sound wave.

I think one possible mechanism for this amplitude dependent sound absorption may be like this:

Most materials (including air) do not follow Hooke's law fully. That is in in simpler terms the restoring force is not proportional to the strain. And as such we can consider sound wave as a strain wave in a medium, the frequency of sound will not be amplitude independent and so hence the sound absorption, as it depends on the frequency and the frequency in turn depending on amplitude, owing to anharmonicity of the medium.

Please correct me if am wrong fully/partially on this as I don't have full self confidence on what I'm thinking is true because sound physics is not my field of expertise like most of you answering here will be experts, I suppose.

Any citation attached will be most appreciated.

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You are right. Like any physical process described by linear equations, there are limits. Think of a sound so intense as to crush the cells in a sound absorbing foam, turning it into a hard surface. A reversible version of that foam is one where the bubbles don't get destroyed, they get flattened to the point that the material they are in starts to play a role, instead of the bubble compression.

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  • $\begingroup$ Thanks for your answer.It has helped me a lot and has made me finally come to a conclusion that sound absorption does depend upon the sound amplitude. $\endgroup$
    – user38220
    Apr 6, 2014 at 21:12
  • $\begingroup$ Very concise, helpful. Nicely put. $\endgroup$
    – Todd
    Jun 29, 2016 at 22:16

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