The Alpine PDX-5 is a 5 channel density digital amplifier with the ability to have 75 watts across 4 channels or focus 300 watts on one. The unit conforms with the rest in the Alpine PDX series when it comes to size, meaning that it can be stacked with any other in the series. However, it is good to note that installing a unit in any other method than parallel to the floor will result in the warranty becoming void. The Alpine PDX-5 offers features such as a 4-Layer glass epoxy PC board, a non-fading pre-amp RCA output, adjustable gain control, a speaker quick connect plug, a subsonic (infrasonic) filter, STAR topology, protection circuits, a power/status LED, a low pass filter, and the same power output for 2Ω or 4Ω loads. The last feature is not offered in many amplifier lines.