Polk's PSW10 powered subwoofer is designed to match with their Monitor Series speakers. The compact enclosure is made from non-resonant MDF with 0.75" internal baffling and bracing for rock solid performance with superlative detail and accuracy.
The voice coil of the 10" driver is perfectly centered in its magnetic field for deep bass with no distortion. The built in amplifier has a 50W continuous output with 100W of peak power. An overall 35Hz to 200Hz frequency response is attenuated by an adjustable 80Hz to 160Hz crossover so you can tune the output to match the rest of your speakers.
There is also a phase switch for additional fine tuning of the sound. The "auto" selection on the power switch lets the subwoofer turn itself off after 15 minutes of no signal and turn itself back an almost instantaneously, leaving you free to enjoy the music and not worry about turning things on and off.