The PS215S offers a trapezoidal dual 15" design with a Nominal Frequency Range from 27 Hz to 500 Hz. This sub is perfectly suited as a rock bass bin, and/or for DJ system applications. Use an Active Electronic crossover such as the LS4-XO model, (pages 9 & 10), or even the built in crossover on our SPA1400C power amp, (pages-3 & 4), to dial in your desired subwoofer crossover point. Of course, the desired frequency may change depending upon your individual situation and or the resonant frequency and acoustics of the room you’re playing in. A good starting point is between 85Hz and 120Hz.