Seashell Effect?

Question

What do you think causes the seashell effect? I think it is partially due to the shell thickness. could it be as the shell wall is thin, sounds are easily absorbed, transmitted and due to the interior smooth surface sounds are reflected within... what do you think? Do you think if thickness of the shell wall plays a part of the effect?

Answer 1

Agree. If the shell were thin, sounds could penetrate. The sound itself is essentially white noise, amplified by the megaphone shape (curled) of the shell