Design: The JL Audio J2 320.4 is 4-channel class B amplifier
rated at 60 watts RMS x 4 into a 4Ω load and 80 watts RMS x 4 into a 2Ω
load. When bridged the output is 160 watts RMS x 2 into a 4Ω load and 120
watts RMS x 2 into an 8Ω load.
Status LEDs: There are two LEDs on the left side of the
- Power: green LED indicates the
amplifier is turned on and operating normally
- Protect: red LED indicates the
amplifier has exceeded its safe operating temperature,
detected a short in a speaker output, or the speaker
impedance is too low
Active Crossover: The front and rear sections of the amp have
individual crossovers. Each can be set to high-pass, low-pass, or off (full range).
The crossover points are also individually adjustable; each high-pass is continuously
variable from 60 Hz to 1.2 kHz and each low-pass is continuously variable from 40 Hz
to 150 Hz. The slope of both crossovers is 12 dB/octave.
Bass Boost: The front and rear sections of the amp also
have separate bass boost circuits. Each is adjustable from 0 to +12 dB; the
boost frequency is fixed at 45 Hz.
Power and Ground: The Power and Ground connections accept 4
gauge wire, which JL Audio recommends as the minimum size. The set-screw terminals
are tightened/loosened using the included 3mm Allen wrench.
Remote Turn-On: The remote terminal will accept 10 to 18 gauge
wire. The set-screw terminal is tightened/loosened using the included 2mm Allen
Speaker Outputs: The speakers' set-screw terminals will accept
8 to 16 gauge speaker wire; they are tightened/loosened using the included 2mm Allen
Preamp Inputs: The amplifier features two sets of RCA line level
inputs. The input sensitivity is adjustable from 200mV to 4V RMS.
Speaker Inputs: When connecting the amp to a head unit without
line level outputs, use the included speaker level input harnesses. In this case
the input sensitivity is adjustable from 2V to 10V RMS.
Preamp Outputs: There is a pair of preamp outputs so you can
send audio to another amplifier in your system. The preamp output is not affected
by the crossover or bass boost circuits.
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