After we set it up in our listening room, the Zvox 325 spread the sound of the phantom left and right "speakers" two to three feet to the sides when we were watching DVDs. The believability of the illusion was superior to those of most single-speaker virtual surround systems we've tested. Surround effects weren't evident from the rear of the room but were projected toward us. All in all, that's impressive performance from a single speaker. Dialogue was natural sounding, without the hollow processing effects we sometimes experience with other virtual surround speakers. The PhaseCue knob on the front panel is adjustable and controls the surround effect--turned all the way down, you just hear the sound of the Zvox 325's three speakers without any processing, but as you turn the PhaseCue up, the apparent soundstage width increases.
Listening to Pat Metheny's brand-new The Way Up-Live DVD in the dark, you'd be hard-pressed to guess all that sound was coming from one speaker. Metheny's unique fusion of acoustic and electric jazz had ample dynamic impact; his nimble guitar textures were vivid, and Steve Rodby's bass was tautly defined. The music is best enjoyed at a healthy volume, and we discovered the Zvox 325 can definitely play loud enough to fill a moderately sized room. As with almost every virtual surround speaker we've tested, the surround is at its best only for listeners seated directly in line with the speaker. Move over to the right or left, and the soundstage collapses into the speaker.
Next we hammered the Zvox 325 with The Fast and the Furious: Tokyo Drift DVD, and marveled at the stamina of the speaker. The whine of high-rpm "rice rocket" cars weren't as audibly powerful as we would experience from a separates-based system, but the Zvox 325 never distorted or broke the spell of the film. And the bass? As far as single-speaker systems go, it's bigger and all around more powerful than any of the other systems we've heard, including the far more expensive Yamaha YSP-series speakers. That said, the Zvox 325 won't fool you into thinking there's a subwoofer lurking in the corner of your room.
Primal Scream's Riot Scream Blues CD blasts off with a Rolling Stones-influenced rocker, "Country Girl." The Zvox 325 kicked pretty hard for just one speaker, although the music sounded noticeably smaller and less expansive than it does over a stereo music or home-theater system. The performance was definitely serviceable--just not as impressive as the Zvox 325 sounded with DVDs.
The Zvox 325 can generate a big sound from a single-box surround speaker system, but if you can accommodate two boxes, the Sharp SD-SP10 virtual surround home-theater system might be an even better alternative for the same price as the Zvox 325 (they're both $350). The SD-SP10 is a two-part speaker/subwoofer system and features Dolby Virtual Speaker technology used in conjunction with Dolby Digital, DTS, and Dolby Pro Logic II surround processing, along with six inputs (three stereo RCA analog inputs, and three digital audio inputs--two opticals and one coaxial). For DVDs, the SD-SP10's subwoofer will exceed the bass capabilities of the Zvox's, and the Sharp's CD sound was also above par. We didn't have the Sharp on hand for direct comparison, so we can't say for sure, but it's at least right up there with the Zvox 325.