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Hertz HMP 4D

Compact 4-channel powersports amplifier — 50 watts RMS x 4

Item # 301HMP4D

Hertz's incredibly tiny and powerful HMP 4D 4-channel amplifier will add new clarity and impact to the basic...

Find what Fits your vehicle

Hertz's incredibly tiny and powerful HMP 4D 4-channel amplifier will add new clarity and impact to the basic...

Item # 301HMP4D

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$379.99

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About the Hertz HMP 4D

Compact power you can hear while splashing

Hertz's incredibly tiny and powerful HMP 4D 4-channel amplifier will add new clarity and impact to the basic sound system of almost any kind of vehicle on land or sea, and it'll fit in a lot of places where space is tight. This marine-rated amp will pump up your system with 50 watts RMS per channel — more than twice the power of most car stereos or marine receivers. You could also bridge this amp to power a couple of subs or high-performance speakers with up to 130 watts RMS each.

Compact power you can hear while splashing

Hertz's incredibly tiny and powerful HMP 4D 4-channel amplifier will add new clarity and impact to the basic sound system of almost any kind of vehicle on land or sea, and it'll fit in a lot of places where space is tight. This marine-rated amp will pump up your system with 50 watts RMS per channel — more than twice the power of most car stereos or marine receivers. You could also bridge this amp to power a couple of subs or high-performance speakers with up to 130 watts RMS each.

This tough guy will make it through the day

The HMP 4D's compact cast-aluminum chassis features IP64 rated protection against water spray, ASTM-D4329 rating for UV resistance, and ASTM-B117 rating for salt fog operability. Balanced high- and low-level inputs ensure that the amp will work in almost any system noiselessly, with no interference. Selectable high- and low-pass filters can tune the music to fit your speakers for superior sound quality.

Hertz HMP 4D

HMP 4D control panel

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Product highlights:

  • compact 4-channel amplifier for ATV, motorcycle, boat, or car
    • 50 watts RMS x 4 at 4 ohms
    • 65 watts RMS x 4 at 2 ohms
    • 130 watts RMS x 2 bridged at 4 ohms
  • Class D amp technology
  • selectable high-pass filter on front channels (full, 65, 85, 115 Hz at 12 dB/octave)
  • selectable high- or low-pass filter on rear channels (full, 65, 85, 115 Hz at 12 dB/octave)
  • IP64 grade protection against water spray, ASTM-D4329 standards for UV resistance, and ASTM-B117 for salt fog operability
More Info:
  • preamp and speaker-level inputs
    • speaker wire to RCA adapters required for speaker-level input
    • signal-sensing turn-on on speaker-level inputs eliminate need for a separate remote lead
  • nature-proof connection cable included
  • wiring and hardware not included with amplifier
    • 10-gauge power and ground leads recommended
  • fuse rating: 15A x 1
  • dimensions: 9"W x 1-3/4"H x 4"D
  • warranty: 1 year
  • Our 60-day money-back guarantee
  • MFR # HMP 4D

What's in the box:

  • 4-Channel powersport amplifier
  • Two 15-amp ATM fuses (one installed/one spare)
  • 2.5mm Allen wrench
  • Four 5/8" Screws
  • User's manual

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More details on the Hertz HMP 4D

Mark G.

Product Research

Features

Overview: The Hertz HMP 4D 4-channel amplifier is effectively two full range 2-channel amps built into one chassis. The front and rear channels are independently bridgeable, so the amp can be wired as 4-channel, 3-channel, or 2-channel.

Control Panel: The control panel is protected by a cover to help keep the controls dry, and prevent unwanted adjustments. The cover screws are removed with the included 2.5 mm Allen wrench. The rotary controls and recessed slide switches require the use of a narrow flat blade screwdriver (not included) to make adjustments. The front and rear sections of the amplifier have independent gain and crossover controls.

  • Input Level: 2-position switch; High (speaker level) or Low (line level)
  • Gain: separate front and rear rotary controls; range is dependent on the input level switch setting; high 800mV to 20V and low 200mV to 5V
  • Front Crossover:
    • Mode: 2-position switch; Full Range or High Pass
    • Frequency: 3-position switch; 65 Hz, 85 Hz, or 115 Hz; 12dB/octave slope
  • Rear Crossover:
    • Mode: 3-position switch; Full Range, High Pass, or Low Pass
    • Frequency: 3-position switch; 65 Hz, 85 Hz, or 115 Hz; 12dB/octave slope

Connections: The power and speaker wires extend 11" from the amp and not terminated.

  • Power: the power wire has an in-line waterproof fuse holder with a 15-amp ATM fuse installed; it appears to be approximately 12-gauge
  • Ground: the ground wire appears to be approximately 12-gauge
  • Remote Turn-on: the remote wire appears to be approximately 16-gauge
  • Speaker Outputs: the four pair of speaker outputs appear to be approximately 16-gauge
  • RCA Inputs: two pair of stereo RCA inputs, each on the end of 6" pigtails; compatible with preamp level and speaker level signals (speaker wire to RCA adapter required when using speaker level inputs)

Specifications:

  • Power Output: at 14.4 volts and 1% THD
    • 4Ω: 50 watts RMS x 4
    • 2Ω: 65 watts RMS x 4
    • Bridged: 130 watts RMS x 2 into 4Ω
  • Additional Specs: Hertz also published the power output at 14.4 volts and 10% THD; 60 watts RMS x 4 into 4Ω and 75 watts RMS x 4 into 2Ω
  • Signal to Noise Ratio: 95 dB
  • THD: 0.2% (at 100 Hz into 4Ω)

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Customer Q&A

2 questions already asked

Q
I want to install this to amplify my Hertz HMR 10 marine head unit with 6, 6.5" speakers. Is this unit pretty much "plug and play" with my factory system?
[ Shawn  Apr 05, 2022 ]
1 answer
A
There is a chance that this amp can use the wiring that is already in place to run. If it can, there are some connections that must be done which will require cutting/splicing into the wire. I recommend contacting an advisor by calling 1-800-324-9695 to check the current wiring
[ Paul  Apr 09, 2022 ]  Staff
Q
Does it need line out coverter ?
[ Jeff  Apr 11, 2021 ]
1 answer
A
This amps RCA inputs can also accept speaker level signals. It does not require a line output converter to be installed. It will need adapters like these so the speaker level signal can be gotten into the inputs: https://www.crutchfield.com/S-wOcwIxFKu6A/g_481250/Speaker-Wire-to-RCA-Adapters.html?tp=88136
[ Paul  Apr 28, 2021 ]  Staff

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