JL Audio A1800 - Manual (Page 3)

POWER CONNECTIONS
Before installing the amplifier, disconnect the
negative (ground) wire from the vehicle’s battery.
This will prevent accidental damage to the system,
the vehicle and your body during installation.
The A1800’s “+12VDC” and “Ground”
connections are designed to accept 4 AWG power
wire. 4 AWG is a minimum power wire size for
this amplifier.
If you are installing the A1800 with other
amplifiers and wish to use a single main power
wire, use 2 AWG or larger main power wire for
systems with total power between 700W and
1400W or 1/0 AWG wire for systems with more
than 1400W. This main power wire should
terminate into a distribution block mounted as
close to the amplifiers as possible. The output of
the distribution block will connect to the A1800
with 4 AWG power wire.
Note: that smaller AWG numbers mean bigger
wire and vice-versa (1/0 AWG is the largest, 2
AWG is smaller, then 4 AWG, then
8 AWG, etc.).
To connect the power wires to the amplifier,
first back out the set screw on the top of the
terminal block, using the supplied 2.5 mm hex
wrench. Strip 1/2 inch (12 mm) of insulation from
the end of each wire and insert the bare wire into
the terminal block, seating it firmly so that no
bare wire is exposed. While holding the wire in
place, tighten the set screw firmly, taking care not
to strip the head of the screw.
The ground connection should be made using
the same gauge wire as the power connection (4
AWG) and should be kept as short as possible,
while accessing a solid piece of sheet metal in the
vehicle. The surface of the sheet metal should
be sanded at the contact point to create a clean,
metal-to-metal connection between the chassis
and the termination of the ground wire. For
optimal grounding, we recommend the use of a
JL Audio ECS master ground lug (XA-MGL-1).
Alternatively, a sheet metal screw or bolt can be
used with a star washer.
Any wires run through metal barriers (such
as firewalls), must be protected with a high
quality rubber grommet to prevent damage to the
insulation of the wire. Failure to do so may result
in a dangerous short circuit.
Many vehicles employ small (10 AWG -
6 AWG) wire to ground the battery to the
vehicle chassis and to connect the alternator’s
positive connection to the battery. To prevent
voltage drops, these wires should be upgraded
to 4 AWG when installing amplifier systems
with main fuse ratings above 60A.
FUSE REQUIREMENTS
It is absolutely vital that the main power
wire(s) to the amplifier(s) in the system be
fused within 18 inches (45 cm) of the positive
battery post connection. The fuse value at each
power wire should be high enough for all of the
equipment being run from that power wire. If
only the A1800 is being run from that power wire,
we recommend a 80A fuse be used. ANL (big
blade fuse), AGU (big glass fuse) or MaxiFuse™
(big plastic-body fuse) types are recommended.
No fuse is required or recommended directly
before the amplifier power connection. If one is
desired, we recommend the use of a 80A AGU,
AFS or MaxiFuse™ type.
JL AUDIO A1800 5
PRODUCT DESCRIPTION
The JL Audio A1800 is a monoblock subwoofer
amplifier utilizing proprietary and patented
Class D technology. Its frequency response
is limited to the range below 250 Hz. It is not
designed for driving midrange speakers or
tweeters. Every aspect of its operation has been
optimized for low-frequency amplification.
For detailed specifications, please refer to
Appendix C (page 13).
TYPICAL INSTALLATION SEQUENCE
The following represents the sequence
for a typical amplifier installation, using an
aftermarket source unit or OEM Interface
processor (like the CleanSweep CL441dsp).
Additional steps and different procedures may
be required in some applications. If you have
any questions, please contact your authorized
JL Audio dealer for assistance.
1) Disconnect the negative battery post
connection and secure the disconnected cable
to prevent accidental re-connection during
installation. This step is not optional.
2) Run power wire (minimum 4 AWG) from the
battery location to the amplifier mounting
location, taking care to route it in such a
way that it will not be damaged and will
not interfere with vehicle operation. Use
2 AWG or 1/0 AWG power wire and a power
distribution block if additional amplifiers are
being installed with the A1800.
3) Connect power wire to the positive battery
post. Fuse the wire with an appropriate fuse
block (and connectors) within 18 inches (45
cm) wire length of the positive battery post.
This fuse is essential to protect the vehicle.
Do not install the fuse until the power wire
has been securely connected to the amplifier.
4) Run signal cables and remote turn-on wire
from the source unit to the final amplifier
mounting location.
5) Run speaker cables from the speaker systems
to the amplifier mounting location.
6) Find a good, solid metal grounding point
close to the amplifier and connect the
negative power wire to it using appropriate
hardware (use of the JL Audio ECS master
ground lug, XA-MGL-1 is recommended).
Use the same size power wire as the wire
connected to the “+12VDC” connection
(4 AWG), no longer than 36 inches (90 cm)
from the amplifier to the ground connection
point. In some vehicles, it may be necessary to
upgrade the battery ground wire. (See page 5
for important notice).
7) Securely mount the amplifier using the
supplied screws.
8) Connect the positive and negative power
wires to the amplifier. A fuse near the
amplifier is not necessary.
9) Connect the remote turn-on wire
to the amplifier.
10) Connect the input cables to the amplifier.
11) Connect the speaker cables to the amplifier.
12) Carefully review the amplifier’s control
settings to make sure that they are set
according to the needs of the system.
13) Install the power wire fuse (80A for a
single A1800) and reconnect the negative
battery post terminal.
14) Turn on the source unit at a low level
to double-check that the amplifier is
configured correctly. Resist the temptation
to crank it up until you have verified the
control settings.
15) Make necessary adjustments to the input
sensitivity controls to obtain the right
overall output and the desired balance
in the system. See Appendix A (page 12)
for the recommended input sensitivity
setting method.
16) Enjoy the fruits of your labor with your
favorite music.
4 JL AUDIO A1800