The thing I love most about multichannel sound is that each speaker is generally required to reproduce fewer instruments or vocals. There is a recent trend in pro audio to have more than two main sound systems, putting some instruments in one, some in the other - basically an offshoot and simplification of the Grateful Dead's "Wall of Sound" where each instrument had it's own set of amplifiers and speakers. When Dave Rat of Rat Sound used what he called a "double hung" system with the Red Hot Chili Peppers, The outer stereo speakers reproduced guitar, bass, toms and cymbals and the inner speakers reproduced vocals, kick and snare. Since no single instrument or vocal was sent to both systems, comb filtering and interference issues were avoided while system clarity was increased. Rat, along with John Meyer, is actually pushing the envelope in sound reproduction. He was also a pioneer in cardioid subwoofer placement which has dramatically increased clarity in stadiums and arenas. By not asking one speaker to reproduce quite as many different sounds, each speaker can do a better job.