XDv2 Series: The JL Audio XDv2 amplifiers feature big audio
performance from a small footprint. With advanced NexD switching technologies,
the XDv2 amps exceed 80% efficiency, running cooler than most other amplifiers.
The Advanced Thermal Rollback System gives you increased reliability and better
audio performance by virtually eliminating thermal shut-down. Because the XDv2
amps employ smaller cast alloy heat sinks, they can be installed in smaller
spaces. XDv2 amplifiers feature a black powder-coat finish with a brushed
aluminum cover for the controls.
Four-channel Class-D Amplifier:
The XD400/4v2 is a Class-D 4-channel amplifier, designed specifically for
full-range operation, but can be used to power subwoofers. The amplifier is
stable down to 2 ohms in stereo, or bridged to a 4 ohm load.
Amplifier Rating: The XD400/4v2 is rated at
75 Watts RMS x 4 channels at
4-ohms (20 Hz to 20 kHz), Signal-to-Noise Ratio of >104 dB (at rated power), 1% THD, @14.4 Volts. At
2 ohms, the rated power is 100 Watts RMS x 4, and bridged at 4 ohms, it outputs
RMS x 2.
Advanced Rollback Protection: The XDv2-Series amplifiers employ advanced
thermal and low-impedance protection to virtually eliminate annoying amplifier
shut-down events. Should any XDv2-Series amplifier ever overheat, its intelligent,
unregulated power supply reacts by limiting available peak voltage until the
amplifier returns to a safe temperature range. Likewise, if an impedance lower
than optimal for the amplifier is present at the outputs, the XDv2 amplifier will
roll back peak voltage to protect itself without shutting down.
Differential-Balanced Inputs: The XD400/4v2 features
differential-balanced input architecture to effectively control noise and ensure
compatibility with a wide variety of source units, including many OEM
systems. Without resorting to line output converters, you can directly connect
most OEM source units to the amplifier 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. This eliminates any voltage sensitivity between one input
terminal and ground and greatly reduces the incidence of alternator whine in a
typical car audio installation.
Note: You will need a
Speaker Wire to RCA adapter (sold separately) for each pair of channels to connect this amplifier to your head unit via speaker level.
Protection Circuitry With Status Indicator Lights: There is
a single multi-color LED on the top panel of the amplifier to indicate the
amplifier's operating status.
- Flashing Green: When
the LED is flashing green, the amplifier is powering up and audio output is
- Constant Green: This LED lights green to indicate that the
amplifier is turned on and operating normally.
- Constant Red: This Red LED lights to indicate that the amplifier
has exceeded its safe operating temperature, putting the amplifier into a
self-protection mode, which reduces the power output of the amplifier. The
red light will shut off and the amplifier will return to normal, full-power
operating mode if the heat sink temperature drops back to a safe level.
- Constant Amber (Yellow): The Amber (Yellow) LED light indicates that an over-current condition has occurred and is accompanied by a muting of the amplifier's output.
Over-current condition can be caused by a speaker impedance lower than the
optimum load impedance range for the amplifier or a short-circuit in the
- LED Off: The only condition that will shut down an undamaged
XD400/4v2 completely is if battery voltage or remote turn-on voltage drops
below 10 Volts. The amplifier will turn back on when voltage climbs
back above 11 Volts.
Cooling System: The outer shell of the JL Audio amplifier is designed
to remove heat from the amplifier circuitry. For optimum cooling performance,
this outer shell should be exposed to as large a volume of air as possible.
Enclosing the amplifier in a small, poorly ventilated chamber can lead to
excessive heat build-up and degraded performance.
Control Panel Cover: The
XD400/4v2 features a brushed aluminum Control Panel Security Cover which protects and hides the
amplifier's controls. When installed, the cover ensures that the amplifier's
settings are not accidentally changed while creating a clean aesthetic look for
the amplifier and your installation. The control panel security cover is
pre-installed at the factory and must be temporarily removed to access the
amplifier's controls. The security cover is secured by two 2.5mm hex-head
Simplified Gain Setting: This XDv2 Series amplifier makes
setting the gain level of the amp via the input sensitivity control very simple.
All you need is
Digital AC Voltmeter and a
Test Disc with a sine-wave test-tone recorded at 0 dB reference level in
the frequency range to be amplified for that set of channels (50 Hz for
subwoofers, 1 kHz for a midrange application). Each pair of channels has a
separate Input Sensitivity control.
Flexible Input Section And Active Crossover Network: The
amplifier provides a flexible input section and a comprehensive crossover
network to fine tune your system effectively and accurately. This 4-channel
amplifier is divided into two separate pairs of channels, each with their own
- Filter: The front and rear channels are equipped with a
12 dB/octave Butterworth filter which can be configured as a low-pass (LP)
or high-pass (HP) filter, or defeated (OFF). You can set the Filter Mode via
a three-way switch.
- Filter Frequency: The filter frequency can be selected
using the rotary control. The control has forty detented positions for
selecting the precise frequency you desire. There are markings at 50Hz,
60Hz, 80Hz, 120Hz, 200Hz, and 500Hz, plus there is a chart in the Owner's
Manual with the exact cutoff frequency for each detent. You'll need a small
screwdriver (not included) to set the frequency.
Turn-on Options: The Turn-on Mode Switch lets you choose the
method for turning the amplifier on and off:
- +12V Remote Turn-on Lead: The preferred method for turning the
amplifier on and off is by running a turn-on lead from the source unit and
connecting it to the Remote terminal. When +12V is present at the terminal,
the amplifier will turn on. When the +12V is turned off, the amplifier will
shut off. The set screw connector on the Remote terminal will accept 18 AWG
to 12 AWG wire.
- DC Offset-Sensing: The amplifier will turn on and off when the
presence of a very small DC signal (or offset) is detected on the amp's RCA
left channel input. The amplifier will turn off when this DC Offset is no
longer present. This method is designed for high-level (speaker-level) input
signals, not for low-level (line-level) signals.
- Signal-Sensing: The amplifier will turn on and off by detecting
the presence of a full-range audio signal at the left-channel input. The amp
will turn off approximately 30 seconds after the audio signal is no longer
detected. This method is designed for use with high-level (speaker-level)
input signals and not for low-level (preamp level) signals.
Note: When the DC Offset or Signal Sensing turn-on methods are
being used, the amp's Remote terminal can be used as a remote turn-on output
for other amplifiers or accessories in the system.
Additional Controls: In addition to the Input Sensitivity,
Filter Mode/Frequency, and Turn-on Mode controls, the XD400/4v2 has the
following controls under the control panel:
- Preouts From: The pass-through preamp outputs can be
configured two different ways:
- 1&2: The preamp output delivers the same signal
that is connected to the CH 1&2 inputs. This allows channels 3&4 to be
faded without affecting the subwoofer level. If CH 1&2 is faded in this
mode, the signal level of the preamp output will change accordingly.
- Sum: The preamp output will deliver a summed
Front/Rear stereo signal to a subwoofer amplifier, while permitting
fading from the front to rear speaker systems from the source unit. No
loss of signal occurs to the subwoofer amplifier when the system is
faded to the front or rear by the head unit.
- Remote Level Mode: You can assign the operation of the
connected HD-RLC to one or both pairs of channels. This two-way switch lets
you select ALL or 3&4.
- Input Mode: The Input Mode switch lets you send four
discrete channels into the amplifier, or use only two channels to feed all
four amplifier channels. You can set the Input Mode to 4 CH or 2 CH.
This JL Audio XDv2 amplifier features set screw clamp terminals for the power, ground, and remote
turn-on connections. A 2.5mm hex-wrench is supplied for tightening or loosening
the set screws.
- Power and Ground:
The amplifier's set screw clamp Power and Ground
connections are designed to accept up to 4 AWG power wire. JL Audio recommends 8
AWG power and ground wire for this amp.
- Remote Turn-On: The amplifier's set screw clamp turn-on
lead will accept 18 to 12 AWG wire.
Note: The Amplifier is not equipped with a fuse. An
external 40-amp AFS, AGU, or MAXI fuse must be installed on
the power wire. If a wiring kit is used which includes a fuse with a value
other than 40 amps, the original should be replaced with a 40-amp fuse.
Speaker Output Terminals: The JL Audio XD400/4v2 features
four set screw clamp speaker terminals for an easy stereo
connection. You can also bridge the amplifier by connecting a 4 ohm load to the CH1/CH3 positive and CH2/CH4 negative terminals. The terminals will accept 16 to 8 AWG speaker
Preamp Inputs: The amplifier features two sets of
differential-balanced RCA jack inputs with an Input Voltage switch. For preamp
level signals, the switch should be set to LOW. For speaker level signals, the
switch should be set to HIGH. The rotary Input Sensitivity gain control can be
set the amp to the
specific signal source that is feeding it. The amplifier's input voltage range
is 200mV-2V (LOW) and 800mV-8V (HIGH).
Preamp Outputs: The XD400/4v2 incorporates a buffered pass-through preamp output
section, so that additional amplifiers can be easily added to the system. The
preamp output signal is not affected by the amp's Low-Pass Filter. If the Input
Voltage switch is in the LOW position, the level of the Preouts matches the
input signal strength. When the Input Voltage switch is in the HIGH position,
the level of the input signal is attenuated -12dB to produce a line-level signal
at the Preouts. You can select which channels feed the preamp outputs: 1&2 or
Remote Level Control: The amplifier features a standard
RJ-14 telephone connector for adding the optional wired
HD-RLC Remote Level Control (sold separately). The Remote Level Control lets
you control the volume
of the XD400/4v2 from the driver's seat.