Phonak Infinio - Number of microphones

There are two mics under the covers. One between the holes toward one end, and one between the two holes toward the opposite end.

WH

Let’s see if I got it right: Two holes per mic? Is that a Phonak design or do other manufacturers do this as well?

There’s two openings per mic so that you have the same degree of mic opening on the outer face (and therefore symmetrical acoustic properties) when they are worn against the head.

Various manufacturers have done the same for years, Oticon shell sets have featured a side ported front mics for 20 years or more. Other BTE also include a similar layout. Single port mics also have the inherent disadvantage of a single failure point.

Supposedly, you can pass the tiny brush through the holes to clean the mic area. The mics are supposedly mounted below that space.