Features
Controls
Connections
Features
Four-Channel Full-Range Amplifier: The JL Audio 300/4v3 is a
class A/B four-channel, full-range amplifier, rated at 75 watts RMS x 4-channels
into a 1.5Ω to 4Ω load, measured from 20 Hz to 20kHz with a power supply
voltage of 11 to 14.5 Volts. The signal-to-noise-ratio is 108.5 dB and total harmonic
distortion is 0.03%, both at rated power from 20 Hz to 20kHz. The amplifier can also
be bridged to output 150 watts RMS x 2-channels into 3Ω to 8Ω loads.
R.I.P.S. (Regulated Intelligent Power Supply): The JL Audio
R.I.P.S. system ensures consistent power delivery over a wide range of battery
voltages and load impedances, providing the rated power output at any impedance
from 1.5Ω to 4Ω and at any vehicle voltage from 11V to 14.5V.
- Regulated Power Supply: The power supply
adjusts to maintain the amplifier's rated power output and low
distortion operation over a wide range of vehicle voltages
(11V-14.5V), so the amplifier's output remains stable in
real-world car audio situations.
- Intelligent Power Supply: An intelligent
circuit monitors output current to optimize the amplifier's
output power over a wide range of load impedances (1.5Ω
to 4Ω). The R.I.P.S. System detects the actual load
impedance, rather than relying on often inaccurate assumptions
based on a speaker's rated impedance, and adjusts output rail
voltages to deliver consistent output.
RealSink Heat Management: The large cast alloy heat sink's
vertical fins are very effective at dissipating heat from the amplifier via
convection and radiation. This design is achieved through extensive finite-element
analysis, resulting in an amplifier that stays cool under demanding conditions. As
an added cosmetic benefit, the cast-aluminum end-caps replicate half of a heat sink
fin so that when two or more amplifiers are mounted end-to-end, you get a seamless
custom look.
Advanced Rollback Protection: If a Slash v3 amplifier should
ever reach an unsafe temperature, the Advanced Rollback Protection circuit reduces
power until the amplifier cools down, without turning the music off completely.
Absolute Symmetry Class A/B Circuitry: The 300/4v3 amplifier
benefits from patented Absolute Symmetry Class A/B Circuitry technology to maintain
high fidelity with low distortion over a wide range of load impedances. The circuit
employs identical N-Channel MOSFET transistors to push and pull the speaker with
true buffering from the load impedance.
Differential-Balanced Inputs: The amplifier features
differential-balanced input architecture to effectively control noise and
ensure compatibility with a wide variety of source units, including many
OEM systems. Without adding line output converters, you can directly connect
most factory radios without creating any noise or compatibility issues. Unlike
conventional single-ended inputs, the differential-balanced design does not
connect one side of the audio signal to chassis ground, eliminating any voltage
sensitivity between that terminal and ground, and greatly reducing the incidence
of alternator whine in a typical car audio installation.
Protection Circuitry with Status Indicator Lights: There are
three status indicator lights on the top of the amplifier:
- Power (Green): lights green to indicate
the amplifier is on and operating normally
- Thermal (Red): lights to indicate the
amplifier has exceeded its safe operating temperature, putting
the amplifier into a shelf-protection mode, which reduces the
power output of the amplifier; the red light will turn off and
the amplifier will return to full-power operating mode when the
internal temperature returns to a safe level
- Low Ohm (Amber): lights to indicate the
impedance of the speaker load is lower than optimum; when this
light is on, a protection circuit engages and reduces the power
output of the amplifier; the amber indicator will also light
when a short-circuit is detected in the speaker wiring
Note: The only condition that will shut
down the 300/4v3 completely is the battery voltage dropping
below 10 volts.
Controls
Gain: The front and rear amplifier sections have independent
gain controls, continuously variable from 200mV to 8V (200mV to 2V with the Input
Voltage switch in the Low position, 800mV to 8V with the Input Voltage switch in
the High position). The amplifier's R.I.P.S. feature also offers an easy way to
optimize the gain setting. Because the amplifier will always deliver the same
amount of power within its operational impedance range and supply voltage range,
the maximum, unclipped output is predictable. This makes setting the gain level
of the amplifier via the input sensitivity control very simple. All you need is
digital AC voltmeter (item number
142TK12V, sold separately) and a test disc with a sine wave test tone recorded
at 0 dB reference level in the frequency range to be amplified (item number
503CD104, sold separately).
Active Crossover: The front and rear amplifier sections also
have independent crossover controls:
- Filter Mode: three position switch; Off
(full-range), LP(low-pass), or HP (high-pass)
- Frequency: rotary dial, variable from 50
Hz to 500 Hz or 500 Hz to 5 kHz (depending on the frequency
range switch)
- Frequency Range: two position switch to
specify the crossover frequency dial range; 50 Hz to 500 Hz
(x1) or 500 Hz to 5 kHz (x10)
- Filter Slope: two position switch to
specify the crossover slope; 12dB/octave (Butterworth) or
24dB/octave (Linkwitz-Riley)
Input Mode: The amplifier's input mode switch allows you to
choose between 4-channel and 2-channel mode. The 4-channel mode requires that
two pair of RCA inputs be connected to the amplifier's front and rear inputs,
while the 2-channel mode only requires one pair connected to the front inputs.
Not front to rear fading is possible in the 2-channel mode.
Connections
Power and Ground: The amplifier's set-screw power and ground
connections accept up to 4-gauge wire. JL Audio recommends 4-gauge for any power
wire longer than six feet (8-gauge is acceptable if the power wire is shorter than
six feet).
Note: The Amplifier is not equipped with an
internal fuse. An external 40-amp fuse (not included) must be
installed on the power wire. If the system has only this amp
and a wiring kit is used that includes a fuse with a value
other than 40-amps, the original should be replaced with a
40-amp fuse.
Remote Turn-On: The set-screw remote terminal accepts up to
8-gauge wire.
Speaker Outputs: The four pair of set-screw speaker terminals
accept up to 8-gauge speaker wire.
Signal Input: The amplifier features two pair of stereo RCA
inputs (front and rear). If no line level signal is available, you will need two
speaker wire to RCA adaptors (item number
136XDCLR2S, sold separately) to connect the amplifier to the source unit via
speaker wires.
Note: All inputs, outputs, and controls are
located on the front side of the amplifier to make installation
of the amplifier simple and neat.
