Sound system with a speaker box having multiple speaker units

Presented is a surround sound system including a loudspeaker enclosure containing a left speaker, a right speaker, and a center speaker. The speakers receive separate audio signals previously processed by a channel decoder. A virtualizer performs a head related transfer function (HRTF) on at least two audio channels. First and second summers respectively combine a front L signal with a post-HRTF L signal, and a front R signal with post-HRTF R signal. The respective combined front L and front R signals are then provided through respective amplifiers to the front L speaker and the front R speaker so as to produce front and rear signals. In another aspect, a loudspeaker enclosure contains first and second left speakers, first and second right speakers, and a center speaker. Wherein the second left speaker and the second right speaker receive respective left surround and right surround post-HRTF virtualizer audio signals.