The rock solid Ultra-Fi™ MOSFET outputs are selected for both balance and output power. Hifonics Brutus BXX4000.1D Class D 4000 Watt RMS Mono Car Amplifier. Authorized Hifonics Dealer! At very high listening levels, Hifonics amplifiers with Super D-Class circuitry result in lower distortion, higher current efficiencies and less heat than conventional D-Class amplifier designs.
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