Hertz HCP 4D

Features

Overview: The Hertz HCP 4D is a 4-channel D-class car amplifier that can drive up to two pairs of speakers or subwoofers. It is part of the Hertz Compact Power (HCP) series, that features compact chassis and minimized extruded aluminum heat sinks. Heat is transferred away from the internal components and out to the heat sinks where it is dissipated through the sides of the amp. The HCP 4D has both speaker-level and line-level inputs to accommodate factory and aftermarket head units.

CEA-2006 Power Output: The HCP 4D is compliant with the CEA-2006 Amplifier Power Standard, which makes it easy for consumers to compare amplifier power specs from one brand to another. The amplifier's CEA-2006 ratings include:

• RMS Power (4Ω, ≤ 1% THD+N, 14.4 volts): 70 watts x 4
• S/N Ratio (ref. 1W output): 80 dBA

Hertz Power Output Specs: Hertz publishes the following power output specs:

• RMS Output Power (14.4 volts, THD 1%):
  • 4 Channel: 75 watts x 4 (4Ω stereo)
  • 4 Channel: 130 watts x 4 (2Ω stereo)
  • 3 Channel: 75 watts x 2 (4Ω stereo) + 260 watts x 1 (4Ω bridged)
  • 3 Channel: 130 watts x 2 (2Ω stereo) + 260 watts x 1 (4Ω bridged)
  • 2 Channel: 260 watts x 2 (4Ω bridged)
• RMS Output Power (14.4 volts, THD 10%)
  • 4 Channel: 85 watts x 4 (4Ω stereo)
  • 4 Channel: 145 watts x 4 (2Ω stereo)
  • 3 Channel: 85 watts x 2 (4Ω stereo) + 290 watts x 1 (4Ω bridged)
  • 3 Channel: 145 watts x 2 (2Ω stereo) + 290 watts x 1 (4Ω bridged)
  • 2 Channel: 290 watts x 2 (4Ω bridged)

Auto Remote Turn-On (ART): The HCP 4D features ART (Auto Remote Turn-On) which automatically powers on and off the amplifier when an audio signal (or lack of one) is detected on the speaker-level inputs. This is especially helpful when connecting the amplifier to an OEM radio. It eliminates the need for running a remote lead from the head unit to the amp. ART is only available with Speaker Level inputs.

Amplifier Controls: The versatile Hertz HCP 4D has a full array of filters and controls to help you configure your audio system for maximum performance. The controls are located on one end of the amplifier, and include the following:

• Level: The rotary Level control lets you match the input of the amplifier to the output of your head unit. The amp will accept either line level (RCA) or speaker level (harness) inputs. The sensitivity range is 0.2V to 5V (preamp level) or 0.8V to 20V (speaker level). There are separate Level controls for the Front and Rear channels.
• Pass Mode: The amplifier has selectable low pass and high pass filters. This 3-way switch lets you choose Full (no filter), Hi (high pass, variable from 50 to 3200 Hz), or Lo (low pass, variable from 50 to 3200 Hz). There are separate Pass Mode switches for the Front and Rear channels.
• Filter: When the Pass Mode is set to Lo or Hi, this rotary dial lets you set the cut off of the crossover between 50 to 3200 Hz. It has a slope of 12dB/octave. There are Filter controls for both Front and Rear channels.
• (In L) Mono: If you want to feed both of the front and/or rear channels with a single mono input, you can turn on the Mono operation mode by pressing in this 2-way button. The inputs should be plugged into the front and rear Left channel input.
• Rear In: If you are connecting four channels of input to the amplifier, you should turn the Rear In switch to On. If you are connecting only two inputs, turning the Rear In switch to Off allows the amp to send the input signal to the rear channels, as well as the front. You will lose front-to-back fading capability if Rear In is turned off.
• Bass Boost: The HCP 4D offers a variable bass boost on the rear channel only to increase the output at 50Hz. This rotary control lets you dial in the amount of desired boost up to +12dB.
• Auto Turn-On: You can activate or deactivate the ART (Automatic Remote Turn-On) feature with the 2-way push button.

Connections: The HCP 4D has the following connections:

• Power/Ground/Remote Turn-on: The amplifier is equipped with set-screw type terminals for power, ground, and remote turn-on. The power and ground terminals will accept up to 4 AWG wire, while the remote terminal will accept up to 10 AWG wire. In most cases, 8 AWG power and ground wires are recommended. Typically, an 18 AWG remote turn-on lead is used, unless the Automatic Remote Turn-on (ART) is used. The set screws can be tightened/loosened with the supplied 4mm or 2mm Allen wrenches.
• Fuses: Two 20A ATO (blade type) fuses are installed in the amplifier. Two spare fuses are also included. A 40A fuse should be placed within 18" of the battery on the +12V power wire as well.
• Speaker Outputs: The amp provides set screw terminals for four speakers. The minimum impedance of the connected load is 2Ω. The set screws can be tightened/loosened with the supplied 2mm Allen wrench.
• RCA Input: Two stereo RCA inputs are provided for connecting an aftermarket head unit to the amplifier. Mono connections for the front and rear channels can be made by plugging the RCA cables to the left channel only, and engaging the Mono Input feature (pressing in the In L (Mono) button). The inputs will accept a signal between 0.2V and 5V.
• RCA Output: Stereo RCA outputs allow you to pass on the signal to another amplifier. The preamp output signal is full-range (or matches the input signal).
• Speaker Input: The front and rear speaker inputs, labeled "Hi In," have 4-pin female Molex connectors. The source unit's speaker wires (L/R Front and L/R Rear) should be spliced to the Speaker Input harnesses. The included harnesses are 7" in length and have a male 4-pin Molex plug. The speaker inputs will accept a signal between 0.8V and 20V.

Additional Specifications:

• Power Supply: 11-15 Volts DC
• Idling Current: 1.6A (on); 0.04 mA (off)
• Consumption (2Ω, 14.4V Max Musical Power): 22A
• Remote In: 7-15 Volts DC / 1mA
• Frequency Bandwidth: 10Hz to 60kHz
• Distortion - THD (100Hz at 4Ω): 0.02%
• S/N Ratio (A-weighted at 1V): 100dB
• Damping Factor (100Hz at 4Ω): 200