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JBL Grand Touring Series II amplifiers create a sound and sight sensation. The aggressively modern amplifier case features a see-through cover which allows you to install internally-mounted neon tubes for an entrancingly cool backlighting effect.

The GTO75.4 II 4-channel amplifier incorporates an efficient power supply that delivers a big sound with low distortion. The variable frequency filters adjust the amp's output to best fit your system's specific needs, whether you're powering full-range speakers or a pair of subs.

The convenient top-mounted controls make it easier to set up and tweak your amp, while preamp outputs simplify adding another amp into your system. The preamp- and speaker-level inputs allow you to add this amp to almost any system, even a factory stereo.

Product Highlights:

  • 4-channel car amplifier
  • 104 watts RMS x 4 at 4 ohms (142 watts RMS x 4 at 2 ohms)
  • 284 watts RMS x 2 in bridged mode (4-ohm stable in bridged mode)
  • optional internal neon lighting (accommodates Street Glow AN9 tubes or equivalent, tubes not included)
  • variable high- and low-pass filters (32-320 Hz, 12 dB per octave)
  • bass boost (0-12 at 50 Hz)
  • MOSFET power supply
  • preamp-level inputs and outputs
  • speaker-level inputs
  • CEA-2006 compliant
  • fuse rating: 30A x 2
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • 16-5/16"W x 2-3/8"H x 12-3/8"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

JBL Grand Touring Series GTO75.4 II Reviews

Average Customer Review:

1 Review

Completely satisfied!

Written by: Anonymous from California on July 16, 2015

Great-sounding multi-channel amplifier. It's traveled through three vehicles without missing a beat. Easy to wire and tweak the output.

Pros: Fidelity & ease of install/instructions.

Cons: Size, but pushing this many watts, something of quality will be large, so it comes with the territory.

Hands-on research

What's in the box?

Download owner's manual

  • 4-channel amplifier with two 30A fuses inserted into the chassis
  • 2 Extra 30A ATC fuses
  • 4 Self-tapping screws
  • 4 Neon tube mounting clips (neon tubes are an optional accessory)
  • Two 11" speaker-level input harnesses
  • Owner's manual
  • Amplifier Quick-Start Guide
  • Warranty Card
  • "JBL" sticker

Product Research

Inputs and Outputs Notes


Internal Crossovers: The amplifier's internal front and rear crossovers are 12dB/octave filters, independently selectable for high-pass, low-pass, or flat (full range) operation. Each crossover is variable from 32 Hz to 320 Hz.

Bass Boost: For added low frequency performance, the rear channels have a 0 to +12 dB variable bass boost centered at 50 Hz.

Preamp Outputs: The preamp output jacks provide a convenient source for daisy-chaining an additional amplifier without running an extra set of RCA cables from the front of the vehicle to the amplifier location. These outputs provide a full-range signal.

Protection Circuitry: To keep the amplifier safely operating, the protection circuitry is triggered in the following situations: DC voltage on amplifier output, overheating, over voltage, under voltage, and when there is a short circuit in the system.

Optional Neon Tubes: Using the supplied mounting clips, you can install optional Street Glow AN9 neon tubes in the amplifier. The neon tubes are installed by removing the amplifier's top panel, which is transparent plastic.

Inputs and Outputs Notes

Power Connections: The power and ground terminals are set-screw terminals and will accommodate up to 4-gauge wire. The remote turn-on terminal will accept up to 8-gauge wire. A Phillips-head (not supplied) is required to tighten/loosen the terminals.

Speaker Connections: The set-screw speaker terminals will accommodate up to 8-gauge wire. A Phillips-head (not supplied) is required to tighten/loosen the terminals.

High Level Input: The amp has two speaker-level inputs, one for the front channels and one for the rear channels. Each input has a 4-pin jack for use with the supplied harnesses.

Our Product Research Team

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