LD Systems ICOA SUB 15A 1,600W Powered 15" Subwoofer400W RMS 1,600W peak Class D power amp boasts a 131dB maximum SPL 15 inch woofer and optimized bass reflex ports yield low end all the way down to 36Hz Proprietary DynX DSP give you distortion free sound at maximum volume 4 intuitive sound presets ensure perfect balance with the rest of your system Switchable signal polarity Delay line function compensates for distances up to 33 feet Excursion limiter, over voltage, over current, peak limiter, and