The patented ME-16R Hot Mic® evolved from many years of research and development to design a true noise canceling microphone that can withstand the harsh marine environment. Many off-the-shelf elements have been used in diving helmets and full face masks (ffm), but require some sort of protection. The protection usually compromises the quality defeating its use. The Hot Mic has proven itself time and time again on many movie sets and Search & Rescue operations. The sound quality produced using a Hot Mic is second to none.
How does it work? A special membrane is used on both sides of the diaphragm which allows air, but not water, to enter. This allows the microphone to cancel noise that is more then 1/4" away. Noise such as air, bubbles and breathing sounds are virtually eliminated. This is especially noticed when using a full-face mask with an oral-nasal cavity. We have been contracted many times to help produce TV and/or Motion Pictures when studio-quality sound is a must.
Can the microphone element be damaged? Yes, the microphone has its limitations. The membrane is designed to allow a user to take the mask off at the back of the boat while in the water. In the past, microphones being exposed to sea water had a short life. Also, when cleaning a ffm, water damaged the old style microphone elements, not so with a Hot Mic. However, the Hot Mic® element can only withstand a differential pressure of about 12'. This means if a diver takes off the ffm at the back of the boat and drops down to 15', the membrane will not be able to keep the water out and the microphone element will be damaged. In our tests, we made several dives to 35' and took off an AGA ffm with a Hot Mic. After putting it back on and clearing it, communications were fine. However, if you took the full face mask off at 35' and dropped down to 47', the membrane would be compromised. We also found if you expose the Hot Mic at any depth down to 130' and come up, no damage will occur.
Conclusion: The Hot Mic will give you the finest intelligibility available and last for months with little maintenance.