A phenomenon that occurs when humans speak words that require a complete closure of the oral passage followed by the release of a burst of air. This commonly occurs in everyday speaking. Sounds like the “P” in the word “pit” or the “D” in “dog” will produce a sudden burst of air from the mouth. If you place your hand in front of your mouth and make these sounds you will feel the burst of air. These sudden movements of air can be a real problem for sensitive microphones recording vocals. To a microphone this mammoth air movement will sound like a loud, bassy pop or thumping sound. Pop filters are commonly used in recording sessions to reduce this problem.