The SUB 15 Universal from Blue Sky International is a 15-inch sealed box subwoofer with a forward-firing driver in a cast-aluminum frame with dual 2.5-inch voice coils. This 1000W subwoofer offers a switchable low frequency response, with the "extended" mode reaching all the way down to 20Hz. This mode is ideal for use in larger rooms that don't provide the same room gain of smaller spaces.

The SUB 15 Universal also has 2.1 bass management electronics built-in, including a 4th order 80Hz Linkwitz-Riley low-pass filter and a 2nd order 80Hz high-pass filter, compatible with the SAT 5, 6.5, and 12 monitor speakers. This allows you to add true low frequency extension to your current near and midfield monitors.