The gain of a hearing instrument can be defined as:

The gain of a hearing instrument is defined as the range of amplification provided. It refers to the increase in sound level that the hearing aid produces compared to the input level of the sound it receives. This measurement is crucial because it indicates how effectively the device can amplify sounds for a user with hearing loss, allowing them to perceive softer sounds more clearly.

Understanding gain is fundamental for hearing aid fitting and adjustment, as it helps audiologists and hearing aid specialists tailor the amplification levels to meet the specific needs of the individual user. The position of gain on a performance curve can illustrate how much louder the device will make sounds across different frequencies.

While the maximum output level pertains to the loudest sound a hearing aid can produce without distortion, and energy efficiency refers to how effectively the device uses power, neither directly describes gain. Clarity of sound produced relates more to sound quality and fidelity rather than the quantitative aspect of sound amplification represented by gain.