Pop Filter
Definition
A physical screen placed between a vocalist and a microphone to reduce plosive sounds — the explosive bursts of air produced by consonants such as "p" and "b." Typically made of nylon mesh or perforated metal, positioned 5–10 cm from the microphone capsule.
In Simple Terms
The round screen you see in front of studio microphones. It stops the burst of air from "p" and "b" sounds from hitting the mic and creating a loud, low-frequency thump. Costs almost nothing but makes a huge difference in vocal recording quality.
In Practice
Without a pop filter, a close-mic'd vocal recording exhibits severe plosive distortion on every word beginning with "p" or "b" — a low-frequency burst that overwhelms the signal. A pop filter placed 8 cm from the capsule eliminates this problem entirely.
Common Confusion
A pop filter is not the same as a foam windscreen. Foam windscreens reduce wind noise outdoors but are less effective at stopping plosives than a proper pop filter for studio vocal recording.