By your description, it sounds like you are using dolby pro-logic for surround, which has low audio fidelity (stereo left and right front channels, mono rear channels) . Dolby pro-logic II has much improved fidelity with stereo left and right rear channels as well as the front channels. For quality sound in surround, from worst to best, this is the order : pro-logic, pro-logic II, dolby digital 5.1, DTS, dvd-audio (or super audio CD SACD).
You say you only have 4 speakers. For accurate surround sound, you need 6 speakers......front left, center channel, front right, rear left, rear right, and subwoofer. To cover the surround bases, you also need a receiver that decodes pro logic II, dolby digital 5.1, DTS, and dvd-audio (or super audio CD).
I myself, can play all of the above options.
