MS-551 Compact Sub Woofer and Amp

Model: MS-551 Brand: poly-planar

Poly-Planar MS-551 has all of the same features as the Poly-Planar MS55 with the addition of a dedicated 100 watts peak (50 watts RMS) waterproof amplifier. The amp is made to mount on the back of the speaker, but can also be mounted elsewhere. Great for a situation where you want to add a sub woofer, but don't want to add a separate amplifier to power it.