5515-44 15" Subwoofer + RPB-XL Bluetooth Boombox Speaker

This bundle pairs the largest 4-ohm subwoofer in the 55 Series with the Rockville RPB-XL, a boombox-style Bluetooth speaker built for volume. The MTX 5515-44 is a 15 inch dual voice coil sub rated for 400 watts RMS and 800 watts peak, with frequency response reaching down to 19 Hz for deep, felt bass. Its Inverted Apex surround and radial ribbed t-yoke combine to push higher output while managing heat during long play.

The RPB-XL matches that low-end focus in portable form. It runs a dedicated 18 watt low-frequency channel alongside dual 6 watt tweeters for 30 watts RMS total, with two passive radiators adding punch that most portable speakers cannot deliver. A 4000mAh battery supports up to 32 hours of playback at low volume, dual USB ports let one play audio while the other charges a phone, and two units link wirelessly through TWS mode for stereo sound. A rubberized carry handle makes it easy to move from the garage to the backyard. Between the two, this bundle covers deep bass in the car and loud, bass-forward sound anywhere else.