The marine amplifier HCP 4MDK features a compact design ready to tackle the open water environment, providing tons of clean power. The HCP M heatsink is made from extruded aluminum, a material unmatched for lightness, sturdiness, and heat dissipation. To keep the size to a minimum, the power transistors are placed between the PCB and the upper side of the heatsink where heat is concentrated. The built-up heat is then directed towards special dissipation "fins" along the side of the amplifier. Both the Pre-In and Speaker-In inputs feature a special balanced circuit, ensuring high rejection against electromagnetic interference for noise-free results. The crossover section of the HCP M amplifiers ensures excellent flexibility: fully adjustable Lo-pass, Hi-pass filters with 12 dB / Oct. and 24 dB / Oct. slopes depending on the amplifier model. Bass Boost is also available to enhance low frequencies.