A sound system with speakers that makes music seem to come from several directions at once—almost like it's all around you—is called a stereo. Your older brother should have set aside some money for food and rent instead of blowing his whole paycheck on a new stereo system.
The kind of sound that's layered and three-dimensional is stereo sound, and the machine you use to play this type of recording is also called a stereo. The word is shorthand for stereophonic, which describes something recorded using two or more channels so that the sound seems to surround the listener and come from more than one source. You can also break this word into its Greek roots, stereo, "solid or three-dimensional," and phone, "voice."