STW1600A is a 1600 W subwoofer, dual-amplified, with internal 100 Hz crossover. The crossover is both mono and stereo, so that the subwoofer can be connected to one or two satellites. To contain the size and weight of the subwoofer it has been manufactured with only one 21" speaker (specifically created by Eighteen Sound) with double coils. The speaker is driven by two final amplifiers with class D digital power of 1000W each, which guarantee dynamics and a considerable sound pressure (134 db). Each of the two amplifiers drives one of the two coils working at a power of 800W each, for a total of 1600W RMS. The weight of the speaker is only 65 Kg, half that of the other active subwoofers of this category available on the market.