Although birds can be great pets and require relatively little care compared to larger, four-legged animals, they can also be quite noisy on occasion. And sometimes, to cut down on the chirping or squawking, it's necessary to soundproof birdcages so that all, or at least most, of the noise a feathery friend makes doesn't escape its immediate surroundings. In cases like these, it's possible to drastically cut down on the noise by hanging around the cage thickly padded, blanket-like sheets that absorb sound.
Place the birdcage in a corner of the room, preferably one near a window. Corner placement is necessary because you'll want whatever noise the bird makes to be confined to a small, enclosed area where sounds don't carry. And placing the bird near a window is helpful because many times when birds squawk it's because they're bored or lack visual stimulation.
Cover the back wall of the cage with an audio absorption sheet, which is a thick cloth that's also called a soundproof blanket. The sheets and blankets are an acoustical product made of natural materials, such as cotton, that absorb and reflect sound. They come in various sizes, and are commonly used in the soundproofing of recording studios. They aren't cheap, however. At time of publication, costs range from as much as $75 for a single sheet, or $230 for a five-pack, depending on the retailer.
Attach one or more audio absorption sheets to the sides of the bird's cage. This will prevent sounds from being transmitted or reflected through the cage but still leave the front and top of the cage exposed. The cage should not be completely covered in absorption sheets so the bird will still have a good view of its surroundings.
Place sound absorption sheets across the door to the room the bird is in, so that any noise that happens to escape from the birdcage doesn't escape the room and make it outside. Some soundproofing retailers sell deluxe wall coverings that are a few feet long that can be hung across doors using clips or special knobs and screws.