Quick Overview Small in size yet able to produce powerful and impactful bass, the TS-WX400DA compact active subwoofer is a perfect upgrade for many of today’s vehicles where small size and low power consumption are priorities. Featuring a powerful, built-in 250 W Max (100 W RMS) Class D amplifier, a down-firing 9" x 5.5" rectangular subwoofer, and Pioneer's DIGITAL BASS CONTROL, the TS-WX400DA can be tuned to your listening preferences and vehicle acoustics. The TS-WX400DA also has multiple input options, allowing connectivity to both aftermarket and OE (Original Equipment) car audio systems.