Recording sounds under water is also known as phonography. Special microphones can be purchased for this purpose but you can also turn a normal dynamic microphone into an underwater sound-capturing device. This trick has been used by foley artists to create special effects for movies and television. A latex condom is the perfect solution for waterproofing almost any dynamic microphone. The shape of the condom covers the capsule of the microphone perfectly but is still thin enough to transmit sound waves.
Plug the XLR cable into the microphone before applying the condom so you can seal the XLR connector as well as the microphone.
Roll the condom over the top of the microphone, down the body and over the XLR connector.
Wrap electrical tape tightly around the outside of the condom just below the bulb at the top of the microphone.
Wrap electrical tape tightly around the condom just below the XLR connector.