Identify materials in the room that are highly sound reflective. Common building materials that contribute to high reverberation are concrete, tile, wood flooring, brick and glass.
Obtain and install sound-absorbent materials over those identified in Step 1. Sound-absorbent materials include heavy pleated drapes, fiberglass board, page board, and sprayed-on cellulose fiber. One easy method to reduce reverberation: Cover hard floors with thick carpet, then hang heavy drapes from floor to ceiling.
Reduce reverberation in sound recording applications by placing the microphone very close to the sound source. This will reduce reverberated sound that reaches the microphone. Have vocalists sing with their lips right next to the microphone.
Use a directional microphone with Hypercardioid and Supercardioid patterns when recording to further reduce reverberation. These are types of microphone pickup patterns designed to reject more of the room's ambient sounds.