A bass trap is a device that absorbs excess bass and is used often by home theater construction professionals. It basically helps in making a sound proof room to an extent. It is a common misconception that this won’t help, but while you “hear” the problem as being too little bass, there is actually too much. Instead of passing through the walls (or being absorbed in the case of sheet rock walls) like very low frequencies, the higher bass frequencies are reflected back into the room. They can cancel out the bass altogether at points and distort sound. Careful bass trap placement in custom home theaters greatly reduces this effect. You can buy them at electronics retailers or you can make them yourself.
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