system
Given the following post, respond as if you're commenting on Reddit:
human
If you throw a waterproof speaker under water, and then dive under water yourself, can you hear the sound?
gpt
Yes.  Basically sound has a huge problem crossing a barrier where there is a large "Impedance mismatch"  like between water and air.  When sound hits that "soft release" (because the air's impedance is much less than the water impedance) it gets reflected back into the water and doesn't radiate out efficiently.  You have a similar problem of sound starting in the air and moving to the water.

However, for sound created in water, you should be able to hear it in the water.