Pop filter

A pop filter is a thin screen, usually nylon mesh or a perforated metal disc, mounted on a gooseneck a couple of inches in front of a microphone. Its job is to break up the fast burst of air produced by plosive consonants like p and b before that air blast hits the capsule and causes a low thump.

Without a pop filter, plosives can overload a microphone's diaphragm for a fraction of a second, creating a distracting pop that is hard to remove cleanly in editing without also dulling the surrounding speech. A filter spreads that air pressure out over a wider area so it arrives at the mic as normal sound rather than a shock wave.

Pop filters also offer a secondary benefit of protecting the microphone capsule from saliva and moisture over time, which matters for the longevity of condenser mics in particular. A filter is inexpensive relative to the cost of a microphone, and pairing one with consistent mic distance solves most beginner plosive problems without needing to fix anything in post-production.