The microphones on AirPods can intake audio and on some earbuds, calibrate noise cancellation modes too. However, their location varies by model.
AirPods utilize both inward and outward-facing microphones to make a wide variety of features possible — from crisp calls to effective noise cancellation modes — so knowing the location of the microphones can be critical to attaining great sound. The AirPods lineup includes an assortment of earbuds and a pair of over-ear headphones, and the location of the microphone on a given pair of AirPods depends on the particular model. There are the standard AirPods, which come in three different generations. Next comes the AirPods Pro, an upgrade over the normal version with three noise cancellation modes. The AirPods Max are the only pair of over-ear headphones in the lineup.
The microphone on a pair of AirPods isn’t just used for intaking audio, it is also used for calibrating the noise cancellation modes on some models. Noise cancellation works by listening to and understanding the audio that is within a user’s surrounding environment, and in some cases, the audio inside the wearer’s ear canal. After this audio is analyzed, noise cancellation headphones can produce a sound that is phase-inverted by 180 degrees. This sound cancels out the intrusive audio in the wearer’s environment, and can work really well with AirPods. However, it’s important to know where the microphones are located to get accurate readings.