When it comes to subwoofers, Polk Audio has at least four product lines with models in the sub-$600 price range (including some below just $200). After reviewing 8-inch models in the Monitor and PSW Series--the PSW10 and PSW111, respectively--we decided to check out the equivalent model in the DSW Pro Series.
Budget subwoofers are usually pretty low-tech devices, but Polk endowed its DSW Pro Series models with a slew of new ideas. The DSW Pro 400, for example, features "Feed Forward distortion suppression technology" that's said to preserve the dynamic capability and maximum output capacity of the subwoofer while maintaining low distortion.
The DSW Pro 400's included credit-card-style remote offers some nice customization and control options. The Polk Room Optimizer feature has four room equalization presets--"corner," "short wall," "long wall," and "mid-room"--to correct for room boundary effects, compensating for bass problems caused by room placement. You can also adjust the volume, mute, and phase (to better blend the sub's sound with the satellite speakers). The backlit Polk logo blinks when you raise or lower the sub's volume, and it can be turned from the remote as well. That's a welcome addition, because the bright blue light can be distracting in dark home theaters.
The DSW Pro 400's 8-inch woofer is powered by a 180-watt digital amplifier. The satin black cube cabinet has gently rounded corners and feels well-built. It's also somewhat customizable: if you don't like the default down-firing woofer, you can move the four carpet spikes/rubber feet to the rear, and tip it 90 degrees, yielding a front-firing configuration (with the connection panel then facing downward). Just be sure you unscrew the feet with care--we came close to leaving some scratches with the pliers we used.