U12i-SUB The bass extension should contain a 12 inch long excursion loudspeaker in a bass reflex tuned cabinet. The used loudspeakers should be impregnated weatherproof. The continuous load capacity of the system should be 800 watts. The loudspeaker should have a nominal impedance of 4 Ohm. The usable system bandwidth should be extended down to 38 Hertz (-6 dB) by using the low bass extension. The system should have an omnidirectional radiation characteristic. The maximum peak sound pressure level should be 130 dB, measured with pink noise at a distance of 1 m, under half-space conditions and with a crest factor of 6. The loudspeaker cabinet should be made of birch multiplex and sealed with a weather- and moisture-resistant polyurea coating (PU). The front of the loudspeaker should be provided with a ball-proof protective grille, which is backed with acoustically neutral foam. Its physical dimensions should be 424 mm in width, 580 mm in height and 300 mm in depth. The weight of the loudspeaker shall be 17 kg. The loudspeaker should be connected via two recessed 4-pin SpeakON sockets on the rear panel. The manufacturer's warranty shall be 5 years.