Hertz HCP 4D 4 Channel Amplifier

The Hertz HCP 4D is a four-channel Class-D amplifier from the Hertz Compact Power series, rated 75 W RMS x 4 at 4 ohm and 130 W RMS x 4 at 2 ohm, and it can be reconfigured to run as four, three or two channels from the same chassis.

Key Benefits

• Three usable configurations from one amplifier: 75 W x 4 at 4 ohm, 75 W x 2 plus 260 W bridged for a subwoofer, or 260 W x 2 at 4 ohm.
• 2 ohm stable on all four channels, where it produces 130 W RMS x 4, so it holds up on paralleled or low-impedance speaker loads.
• Very low measured distortion for the class at 0.02 percent THD at 100 Hz into 4 ohm, with a 100 dB A-weighted signal-to-noise ratio and a damping factor of 200.
• Complete, bypassable crossover system: adjustable Hi-Pass and Lo-Pass from 50 Hz to 3.2 kHz at 12 dB per octave, plus bass boost adjustable 0 to 12 dB at 50 Hz.
• Speaker-In inputs take 0.8 to 20 V RMS straight from a factory radio, and RCA Pre-In takes 0.2 to 5 V RMS from an aftermarket deck.
• Small enough to hide: an 8.46 x 7.87 in chassis just 1.97 in tall, weighing 4.27 lb.
• Modest current demand for a four-channel amplifier at 22 A maximum consumption at 2 ohm and 14.4 VDC, on two 20 A fuses.

Fitment

The HCP 4D is a universal 12-volt amplifier rather than a vehicle-specific part. It works with any negative-ground system running 11 to 15 VDC, which covers cars, trucks, SUVs and side-by-sides, and its dual input types mean it drops into a stock or an aftermarket system without an adapter.

Minimum load depends on the mode: 2 ohm per channel in four-channel operation, 2 ohm plus 2 ohm plus 4 ohm in three-channel operation, and 4 ohm when bridged to two channels. Allow for an 8.46 x 7.87 x 1.97 in chassis and size the battery feed for a 22 A maximum draw behind two 20 A on-board fuses.

Model numbers in this family are close, so check yours. The HCP 4D is the standard-power four-channel Compact Power amplifier at 75 W x 4 into 4 ohm and 1160 W total. The HCP 4DK is the higher-power model in the same family, 120 W x 4 into 4 ohm and 2000 W total, on a longer 12.40 in chassis with two 35 A fuses. The HCP 4M is the marine-rated four-channel model. Hertz publishes no IP or salt-fog rating for the HCP 4D, so mount it in a dry, protected location.