Subwoofer series jbl studio power rating 200 watt effective output 400 watt system 1 way system principle active frequency response 32 150 hz crossover frequency 50 150 hz amplifier type digital colour black control features volume control adjustable transition frequency switchable phase control design front firing subwoofer number of subwoofers 1 bass chassis 250 mm bass reflex port position rear firing port analogue input analogue audio input