Do anyone know how to do sound transmitter and recevier?

I have a project in my mind, that using simple sound transmitter to send wave in the water, receive it by recevier?

Do anyone know this schmatics diagram ?
thank u?

Well, to start with, you'll need a waterproof speaker and microphone Try using a speaker with a plastic cone, and waterproof the connections with silicone or something similar. A waterproof microphone? Maybe put it in a plastic zip bag???

need help?

To Phasor :
would u might to pass me some knownledge about the schmatic drawing about sound receiver and transmitter.

Sounds like (no pun intended) sonar - the simpler versions transmit pulses then listen in between the pulses for the echo or return. Frequencies can be ultrasonic (or not) but it's still "sonic" so it seems the technology would apply. "Transducer" is often the name for the speaker or microphone since it's converting electrical energy to sound then sound to electrical energy. Lots of modest cost stuff out there used by fisherman - got to believe some do-it-yourselfers have done it themselves and published info. So - sonar, transducer might be key words to help with a search.

Also, speakers for swimming pools are sold here in US though I am not sure how they are different from generic speakers.

Sounds like (no pun intended) sonar - the simpler versions transmit pulses then listen in between the pulses for the echo or return. Frequencies can be ultrasonic (or not) but it's still "sonic" so it seems the technology would apply. "Transducer" is often the name for the speaker or microphone since it's converting electrical energy to sound then sound to electrical energy. Lots of modest cost stuff out there used by fisherman - got to believe some do-it-yourselfers have done it themselves and published info. So - sonar, transducer might be key words to help with a search.

Also, speakers for swimming pools are sold here in US though I am not sure how they are different from generic speakers.

to stevez:
thank stevez, but do any wedsite introduce sonar system. it is expensive aviliable in singapore.