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Focal Impulse 4.320

Compact 4-channel amplifier — 55 watts RMS x 4

Item # 091IMPULSE

Focal designed their Impulse 4.320 4-channel amplifier to fit almost anywhere inside a vehicle.

Read more from Crutchfield writer, Buck P.

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$299.99

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About the Focal Impulse 4.320

Big power from a tiny amp

Focal designed their Impulse 4.320 4-channel amplifier to fit almost anywhere inside a vehicle. The Impulse 4.320 sends 55 watts RMS to each of your speakers from a chassis that's smaller than a brick. You can also use an Impulse 4.320 in 3-channel mode to power a pair of speakers with 55 watts RMS each while sending up to 160 watts to a sub.

Big power from a tiny amp

Focal designed their Impulse 4.320 4-channel amplifier to fit almost anywhere inside a vehicle. The Impulse 4.320 sends 55 watts RMS to each of your speakers from a chassis that's smaller than a brick. You can also use an Impulse 4.320 in 3-channel mode to power a pair of speakers with 55 watts RMS each while sending up to 160 watts to a sub.

Plays well with other stereos

The Impulse 4.320 comes with input harnesses that let you connect to any aftermarket receiver or a factory radio. Separate filters for the front and rear channels optimize the sound for your speakers and subs. An adjustable phase control on the rear channels comes in handy for tuning a sub's sound to blend in with front speakers.

Focal Impulse 4.320

Controls and connection guide on underside

READ LESS

Product highlights:

  • compact 4-channel amplifier
  • 55 watts RMS x 4 at 4 ohms (80 watts RMS x 4 at 2 ohms)
  • 160 watts RMS x 2 at 4 ohms (bridged mode)
  • CEA-2006 compliant
  • Class D amp technology
  • front channels: switchable high-pass filter (75 Hz)
  • rear channels; adjustable high- or low-pass filter (40-200 Hz) and adjustable phase control (0-180°)
  • preamp and speaker-level inputs
  • wiring, fuse, and hardware not included with amplifier
    • 10-gauge power and ground leads and a 25A fuse recommended
    • for power wire shorter than 10 feet: 12-gauge power and ground leads and a 15A fuse recommended
  • dimensions: 6-15/16"W x 1-7/8"H x 2-5/8"D
  • warranty: 1 year
  • Our 60-day money-back guarantee
  • MFR # IMPULSE 4.320
KEEP READINGREAD LESS

What's in the box:

  • 4-Channel amplifier
  • 9" Power/speaker output harness
  • Two 25A ATO fuses (one installed in in-line fuse holder)
  • 8" Speaker input harness
  • 7" RCA line input harness
  • 2 Mounting brackets
  • User Manual

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Features

Overview: The Focal Impulse 4.320 is an ultra-compact 4-channel amplifier that provides additional power for your OEM or aftermarket car stereo system. Its compact size (7" W x 1-13/16" H x 2-11/16" D) allows you to install the amplifier in or under the dash of most vehicles. The Impulse 4.320 comes with plug-in harnesses to make installation easier.

CEA-2006 Power Output: The specifications given by Focal for the built-in amplifier comply with the CEA-2006 mobile amplifier power testing and measurement standards from the CEA (Consumer Electronics Association). All manufacturers who comply with the standard can display the CEA-2006 logo on their product. The Impulse 4.320 has the following power output specifications:

  • Power Output (4 ohms): 55 watts RMS x 4 channels
  • Power Output (2 ohms): 80 watts RMS x 4 channels
  • Bridged Power (4 ohms): 160 watts RMS x 2 channels

Compatibility: The amplifier is compatible with most aftermarket stereos and factory-installed car stereo systems. The head unit must have either amplified speaker outputs or RCA preamp outputs. OEM head units with separate factory-installed amplifiers are not compatible. The amp's RCA inputs should be used if the head unit has RCA outs. The amplifier's speaker-level inputs are used if the head unit has amplified speaker outputs. An optional Y-cable is available from Focal that gives you Plug & Play compatibility with many OEM head units.

Connections: The Focal Impulse 4.320 4-channel amplifier comes with a variety of harnesses for connecting your head unit and speakers. These harnesses will need to be spliced with other wires before they are plugged into the amplifier. These harnesses include:

  • Power/Output Harness: This 14-conductor harness includes the wiring for +12V, Ground, and Remote Turn-on leads. It also includes the speaker output wires for the four amplifier channels. The connected speakers cannot have an impedance lower than 2Ω. You should use 12-gauge or 10-gauge power wire, depending upon the length of the cable to the battery, with a 25A fuse no more than 18" from the battery.
  • Speaker Input Harness: If you are connecting the amplifier to your head unit's amplified speaker output wires, you will need to splice them to the speaker input harness. The harness plugs into the 8-pin "Inputs" jack, and Input Level switch should be set to "High."
  • RCA Input Harness: If you are connecting the amp to your head unit's RCA preamp outputs, the RCA Input Harness is used. An RCA patch cable will be needed (not included). The harness plugs into the same 8-pin "Inputs" jack (as the speaker input harness), and the Input Level switch should be set to "Low."

Bridging The Amplifier: The Impulse 4.320 can be bridged from 4 channels to 2 to double the output power. On the Power/Output Harness, the Rear Right - (negative) and the Rear Left + (positive) speaker wires will be connected to one speaker, and the Front Right - (neg) and Front Left + (pos) are connected to the other speaker. You cannot bridge the amplifier to a speaker with an impedance lower than 4Ω.

Controls: Amplifier controls are located on one end and on the bottom of the amp:

  • Right End:
    • Input Level Switch: The Input Level Switch lets you select the type of input that is connected to amplifier (High for speaker-level input or Low for RCA input).
    • Front and Rear Gain: Separate rotary gain controls for the Front (Ch 1/2) and Rear (Ch 3/4) channels are provided to adjust the strength of the incoming signal. The Input Sensitivity ranges from 0.2V and 5.0V. A small flat-head screwdriver (not included) will be needed to adjust the gain.
  • Bottom:
    • Front Crossovers: For the Front Channels (1/2), a High Pass Filter (HPF), centered at 75Hz, can be applied, if desired, via a 2-way switch. The switch can be set to 75Hz HPF or Full (for Full-Range output).
    • Rear Crossovers: On the Rear Channels (3/4), you can set the output to Full Range, or apply a Low-Pass Filter (LPF) or High-Pass Filter (HPF) via a 3-way switch. If the Low- or High-Pass filter is applied, you can set the cutoff frequency between 40Hz and 200Hz via a rotary control.
    • Phase: You can set the phase of the rear channel output between 0° and 180° via a rotary control.
    • Input Select: The Input Select can be set via a 3-way switch. To play the Channel 1 and 2 input signal through Channels 3 and 4, select "1/2". For an independent 4-channel input configuration, select "3/4". If you're using a 3-channel configuration (channels 1 and 2 in stereo and bridged mono output for channels 3/4), you should select "1+2".

Protection Circuitry: The Impulse 4.320 is equipped with circuitry designed to protect the amplifier in case of a malfunction or connection error. This protection circuitry will shut down the amplifier in case of any of the following conditions: short circuit, over-current, reverse polarity, DC output, voltage drop, and overheating. A Protect LED will glow red if the amplifier goes into protection mode.

Specifications:

  • Frequency Response: 10Hz to 20kHz (+/- 1dB)
  • Signal-to-Noise Ratio: > 80 dBA
  • Total Harmonic Distortion: THD+N < 0.05% (from 0.5 to 50Wrms at 4Ω, 1 kHz, 22 kHz LPF)
  • Cross-talk: > 65 dB
  • Standby Consumption (Remote ON): 750mA
  • Fuse Ratings: 25A (15A if using RCA inputs)
  • Dimensions: 7" Width, 1-13/16" Height, 2-11/16" Depth
  • Weight: 24.2 ounces

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