In Stock. 45 Day Lowest Price - 100% Satisfaction Guarantee. The ideal complement to dB Technologies' OPERA 110 and TWIN 128 is the 12" active subwoofer in a sexy outfit with exciting technical specifications and powerful thrust. The 12" long stroke woofer with 3" oscillation coil moves up to top form in the band pass housing. The 400W/RMS output stage built up in the new innovative MT Amp provides the necessary propulsion at an extremely low weight.