An aging gentleman suspects that his hearing is failing. he sees a specialist who performs this test to determine the precise nature of his suspected hearing loss.

The answer is "audiometry test".

An audiometry exam tests your capacity to hear sounds. Sounds fluctuate, in view of their uproar (force) and the speed of sound wave vibrations (tone).  

Hearing happens when sound waves animate the nerves of the internal ear. The sound at that point ventures out along nerve pathways to the cerebrum.  

Sound waves can head out to the internal ear through the ear waterway, eardrum, and bones of the center ear (air conduction). They can likewise go through the bones around and behind the ear (bone conduction).

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