underwater listening - bone-conduction

[Andre Castro <andre_castro83@xxxxxxxxxxx>]

Hello, I?m sonic arts student at Middlesex University (UK). I?m currently I 
developing a project on underwater soundscapes. My intention is to create a 
body of recordings of underwater sound environments, with which I can start 
composing with. Although that has not been an easy job, recording in pools, 
ponds and small rivers, using homemade hydrophones both with piezzo 
transducers and dynamic mics. However results have been quite stimulating to 
the work.

One thing that has been fascinating me is the fact that our perception of 
underwater sound is realized through bone conduction. For what I could 
gather by relating different sources is that when inside water the impedance 
matching/communication form the ear drum (air) to the inner ear (fluid), 
through the ossicles is stopped. As a result our air conducted listening is 
also stopped. We no longer perceive sound through the vibration of the 
eardrum, but through the vibration of the skull and jaw.

I do not know until what point this is as it happens, I am afraid I might be 
speculating quite a bit. However doing quite some research (in underwater 
sound, deafness, hearing aids) I haven?t been able to find almost any proper 
information.



I would be very pleased if anyone could give some insight on this subject or 
point me in some direction (book, website, person) how might help in this 
subject.

Cheers,

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