Act ATC – If you're subbing, the Brits heard your call with the new C4 Sub Mk2 [£3'990], a 300-watt class AB Mosfet 12" sealed bass solution. With its underhung voice coil, 30mm long gap and 150mm N48M neodymium motor, long-throw surround and optimized spider, everything about the SS75-314SC woofer is new and purpose-designed for this use. So is the amplifier with dual XLR inputs of 20kΩ input impedance, analog 4th-order Linkwitz-Riley low-pass filters at 50, 60, 80 and 320Hz, 180° phase, +6/10dB gain switch in conjunction with a stepped attenuator for 21dB of precision adjustment range. Finish options are cherry, oak, walnut and black ash veneers as well as satin black or white finishes. For a surcharge, premium options include rarer veneers, high-gloss skins, even black or white piano lacquers. The sub weighs a substantial 42kg and measures 568 x 465 x 519mm HxWxD.