Roswell&&';;s R1 550.2 is the ideal amp to run your R1 Tower Speaker setup. It&&';;s a 2-channel Class-D design that puts out 165 watts RMS per channel at 4 and 275 watts RMS per channel at 2. Featuring calibrated crossover controls, differential RCA inputs for maximum noise rejection, fully conformal-coated PCBs, and nickel-plated marine-grade wire terminals. Each sold separately Continuous Power (RMS) 4: 165W x 22: 275W x 2Bridged 4: 550W x 1Frequency Response 10-25 kHzInput Sensitivity 0.2 - 10.0VHPF (High Pass Filter) 30Hz - 300HzLPF (Low Pass Filter) 30Hz - 300HzBass EQ 0 ~18dB @ 45HzSubsonic Filter 10 Hz - 55 HzPhase Control 0-180degDimensions Inches: 1.90 x 7.0625 x 11.125Centimeters: 4.83 x 17.94 x 28.26