The Hifonics BG-4000.1D BRUTUS GAMMA is a mono subwoofer car audio amplifier built around Super D-Class technology and Ultra-Fi MOSFET output devices, delivering up to 4000 watts for a single subwoofer setup. Its variable electronic crossover, built-in bass control, subsonic filter and 0-180 degree phase adjustment let you dial in the low end, while nickel-plated RCA inputs and high-temperature output connectors keep every connection secure.

Power strapping lets an installer sync the input signal and output power of two amplifiers to double the rated output for a single subwoofer or a group of subwoofers, and the included wired bass remote puts bass frequency adjustments within reach from anywhere in the vehicle. The amplifier measures 21.94 x 11.81 x 4.06 inches and weighs 13.65 lbs.