It is known that sound waves slow down greatly under water, which makes it impossible to hear what is happening on the surface of the water without special devices. However, a group of international experts have developed a simple device that allows you to hear the speech of people who are above the water a few meters from the diver.
The fact is that the loss of an impulse of a sound wave during the transition from air to water is about 30%, which does not allow the human ear to normally pick up sounds. The new device is based on the use of latex particles, which are pulled on aluminum plates located on a special membrane. Such a special membrane is attached to the ear and increases the conductivity by several tens of times, while the sound itself is practically not distorted, allowing you to hear everything that happens above the water surface. Scientists have succeeded in ensuring that losses due to membrane sensitivity are compensated for, and in such a way that these losses ultimately do not exceed 6%.
It is not yet known at what depth and how the new device is planned to be used in general, because it is attached near the external auditory canal, and the diver's ears must remain open for the device to work properly.
Vladimir Kuznetsov