Diver specific scubduck noise

[lhpdiver]

I've been having this recurring thought lately about some sort of device like a scubduck / mini-hammerhead which would have a way to "dial" a sound. Let's say a cat, horse, dog or more cellphone like noises.

I know the world probably doesn't need it.
I know everyone hates these devices.
I know you can bang on your tank.

Can anyone think of a way this might work ?

 

[Allison Finch]

Hmmm....you show up with that on a dive that I am on, I'll be glad I still carry a knife!!!!