JL Audio XD300 User manual

Thank you for purchasing a JL Audio amplifier for
your automotive sound system.
Your amplifier has been designed and manufactured to exacting
standards in order to ensure years of musical enjoyment in your vehicle.
For maximum performance, we highly recommend that you have
your new amplifier installed by an authorized JL Audio dealer. Your
authorized dealer has the training, expertise and installation equipment
to ensure optimum performance from this product. Should you
decide to install the amplifier yourself, please take the time
to read this manual thoroughly so as to familiarize yourself
with its installation requirements and setup procedures.
If you have any questions regarding the instructions in this
manual or any aspect of your amplifier’s operation, please contact your
authorized JL Audio dealer for assistance. If you need further assistance,
please call the JL Audio Technical Support Department
at [phone] during business hours.
OWNER’S MANUAL
300W Monoblock Subwoofer Amplier

2 | JL Audio - XD300/1 Owner’s Manual
Status
LED
(pg. 11)
Filter
Frequency
Selector
(pg. 8)
LP Filter
Mode/Slope
Selection
(pg. 8)
Input Sensitivity
Control
(pg. 7)
PROTECT YOUR HEARING!
We value you as a long-term customer. For
that reason, we urge you to practice restraint in
the operation of this product so as not to damage
your hearing and that of others in your vehicle.
Studies have shown that continuous exposure to
high sound pressure levels can lead to permanent
(irreparable) hearing loss. This and all other
high-power amplifiers are capable of producing
such high sound pressure levels when connected
UPBTQFBLFSTZTUFN1MFBTFMJNJUZPVSDPOUJOVPVT
exposure to high volume levels.
While driving, operate your audio system in
a manner that still allows you to hear necessary
noises to operate your vehicle safely (horns,
sirens, etc.).
SERIAL NUMBER
In the event that your amplifier requires
service or is ever stolen, you will need to have
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take the time to enter that number in the space
provided below. The serial number can be found
on the bottom panel of the amplifier and on the
amplifier packaging.
Serial Number:
INSTALLATION APPLICATIONS
This amplifier is designed for operation in
vehicles with 12 volt, negative-ground electrical
systems. Use of this product in vehicles with
positive ground and/or voltages other than 12V
may result in damage to the product and will void
the warranty.
This product is not certified or approved for
use in aircraft.
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amplifier with the outputs of a second amplifier,
including an identical one.

3
ENGLISH
PLANNING YOUR INSTALLATION
It is important that you take the time to read
this manual and that you plan out your
installation carefully. The following are some
considerations that you must take into account
when planning your installation.
Cooling Efficiency Considerations:
The outer shell of your 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. If an installation calls for an
enclosure around the amplifier, we recommend
that this enclosure be ventilated with the aid
of a fan. In normal applications, fan-cooling
is not necessary.
IMPORTANT
!
Mounting the amplifier upside down is
strongly discouraged.
If mounting the amplifier under a seat,
make sure there is at least 1 inch (2.5 cm) of
space above the amplifier’s outer shell to permit
proper cooling.
Safety Considerations:
Your amplifier needs to be installed in a dry,
well-ventilated environment and in a manner
which does not interfere with your vehicle’s safety
equipment (air bags, seat belt systems, ABS brake
systems, etc.). You should also take the time to
securely mount the amplifier so that it does not
come loose in the event of a collision or a sudden
jolt to the vehicle.
Stupid Mistakes to Avoid
tCheck before drilling any holes in your vehicle
to make sure that you will not be drilling
through a gas tank, brake line, wiring harness or
other vital vehicle system.
t%POPUSVOTZTUFNXJSJOHPVUTJEFPSVOEFSOFBUI
the vehicle. This is an extremely dangerous
practice which can result in severe damage to
your vehicle and person.
t1SPUFDUBMMTZTUFNXJSFTGSPNTIBSQNFUBM
edges and wear by carefully routing them,
tying them down and using grommets and
loom where appropriate.
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compartment, under the vehicle, on the roof
or in any other area that will expose the
amplifier circuitry to the elements.
Remote Turn-On
Connector
(pg. 6)
Chassis Ground
Connector
(pg. 5)
Left & Right
Preamp Output Jacks
(pg. 10)
+12 V Power
Connector
(pg. 5)
Mono
Subwoofer Outputs
(pg. 10)
Jack for
Remote Level
Control Knob
(pg. 9)
Left & Right Preamp
Input Jacks
(pg. 7)

4 | JL Audio - XD300/1 Owner’s Manual
PRODUCT DESCRIPTION
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speed switching technology to deliver
outstanding fidelity and efficiency.
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variety of source units and system configurations.
Its frequency response is limited to the range
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driving midrange speakers or tweeters. Its
operation has been optimized for low-frequency
amplification. For detailed specifications, please
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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)%JTDPOOFDUUIFOFHBUJWFCBUUFSZQPTU
connection and secure the disconnected cable
to prevent accidental re-connection during
installation. This step is not optional.
2) Run 8 or 4 AWG power wire 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 4 AWG or larger
power wire and a power distribution block if
additional amplifiers are being installed with
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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, XB-MGLU is recommended).
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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.
8) Connect the positive and negative power
wires to the amplifier. A fuse near
the amplifier is not necessary if the
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from the fused main power wire. If
the fused main power wire is shared
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or devices, fuse each amplifier/device
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via a fused distribution block or multiple
individual fuse blocks/on-board fuses.
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.
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near the amplifier (if applicable).
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.

5
ENGLISH
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.
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connections are designed to accept 4 AWG
power wire. 8 AWG is the minimum wire size
for this amplifier.
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amplifiers and wish to use a single main power
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power wire (depending on the overall current
demands of all the amplifiers in the system).
This large power wire should terminate into a
fused distribution block mounted as close to
the amplifiers as possible (within 12 inches /
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with 8 or 4 AWG power wire. JL Audio ECS
fused distribution blocks are recommended
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Note: Smaller AWG numbers mean bigger
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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 4 AWG wire 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 (XB-MGLU). 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.
IMPORTANT
!
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
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If fusing the amplifier near its power
connections (when more than one amp is being
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(MAXI™ big plastic-body fuse is recommended).

6 | JL Audio - XD300/1 Owner’s Manual
TURNON LEAD
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turn-on lead, typically controlled by the source
unit's remote turn-on output. The amplifier will
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a source unit does not have a dedicated remote
turn-on output, the amplifier’s turn-on lead can
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power from an ignition-switched circuit.
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connect the remote turn-on wire 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 (12mm) of 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 the terminal, tighten the set
screw firmly, taking care not to strip the head of
the screw and making sure that the wire is firmly
gripped by the set screw.

7
ENGLISH
INPUT SECTION
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you to send signal to the amplifier section
through the use of two differential-
balanced inputs, one for the left channel
signal and one for the right channel signal.
Connection is via RCA-type jacks.
You may run a stereo or a mono signal into
the inputs of the amplifier. The amplifier’s input
section automatically sums stereo signals to mono
for the internal amplifier section. The amplifier
will operate with only one input connection (left
or right), but will require an increase in input
sensitivity to overcome the loss of signal. If a
mono input signal is to be run, we recommend
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signal into both inputs of the amplifier.
Input Voltage Range:
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will accommodate all preamp level signals and
many speaker level signals.
To use speaker-level sources, simply splice the
speaker output wires of the source unit onto a
pair of RCA plugs for each input pair. (or use
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If you find that the output cannot be reduced
sufficiently with a direct speaker level signal
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signal level.
INPUT SENSITIVITY CONTROLS
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to match the source unit’s output voltage to the
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output. Rotating the control clockwise will result
in higher sensitivity (louder for a given input
voltage). Rotating the control counter-clockwise
will result in lower sensitivity (quieter for a given
input voltage.)
To properly set the amplifier for maximum
clean output, please refer to Appendix A (page
12) in this manual. After using this procedure,
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downward if this is required to achieve the
desired system balance.
Do not increase any “Input Sens.” setting for
any channel(s) of any amplifier in the system
beyond the maximum level established during
the procedure outlined in Appendix A (page 12).
Doing so will result in audible distortion and
possible speaker damage.

8 | JL Audio - XD300/1 Owner’s Manual
FILTER CONTROLS
Most speakers are not designed to reproduce
the full range of frequencies audible by the human
ear. For this reason, most speaker systems are
comprised of multiple speakers, each dedicated
to reproducing a specific frequency range. Filters
are used to select which frequency range is sent
to each section of a speaker system. The division
of frequency ranges to different speakers can be
done with passive filters (coils and/or capacitors
between the amplifier outputs and the speakers),
which are acceptable and commonly used
for filtering between mid-range speakers and
tweeters. Filtering between subwoofer systems
and satellite speaker systems is best done with
active filters, which cut off frequency content at
the input to the amplifier. Active filters are more
stable than passive filters and do not introduce
extraneous resistance, which can degrade
subwoofer performance.
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is designed to attenuate frequencies above its
filter frequency, so that the system’s subwoofers
do not reproduce any audible midrange content.
This serves to improve tonal balance
and to avoid distortion. Correct use
of the filter can substantially improve
the fidelity of your audio system.
2) LP Filter Operation: The low-pass filter in the
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features the ability to select between a moderate
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slope via the “LP Filter Mode/SlopewTXJUDI
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the vehicle, different slopes may be required
to produce a smooth transition to the mid-
bass speakers in the system. Experiment to
find the slope which best matches the acoustic
requirements of your system.
Tuning Hint: A trunk mounted sub whose
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back seat often benefits from the 12 dB/octave
slope which lets more upper bass content pass
through. A sub that fires directly into the
listening environment is more likely to benefit
from a 24 dB/octave slope.
Note:5IFBCPWFIJOUJTOPUiTFUJOTUPOFwy
You should always listen to the system carefully to
determine the best choice as vehicle acoustics and
other factors play a big role in choosing the most
appropriate filter slope.
Precise Frequency Selection: The filter
frequency markings on the front panel of
the amplifier are for reference purposes and
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or better. If you would like to select the filter
frequency with a higher level of precision,
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This chart gives you a more accurate frequency
for each of the forty detented positions of the
frequency selection control. This method can
be very useful if the amplifier is mounted in
a location where you can’t see the front panel
markings easily.
4) Defeating the LP Filter:5IF-PX1BTTGJMUFS
can also be defeated completely, by switching
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an external active crossover in the system.
With the internal crossover turned off, the
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9
ENGLISH
REMOTE LEVEL CONTROL OPTIONAL
With the addition of the optional Remote
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subwoofer volume from the front of the vehicle.
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of the amplifier using a standard telephone cable
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When connected to the amplifier, the
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clockwise rotation, the audio will mute
completely. At full clockwise rotation the level
XJMMCFUIFTBNFBTJGUIF)%3-$XBTOPU
connected at all. In other words, it operates
strictly as a level attenuator.
PREOUTS
5IF9%JODPSQPSBUFTBQBTTUISPVHI
preamp output section, so that additional
amplifiers can be easily added to the system.
The preamp output delivers the same signal that
JTDPOOFDUFEUPUIF9%TJOQVUT
The preamp output signal by any crossover
filter selected (if the input signal is full-range, the
preamp output will be full-range).
IMPORTANT
!
If you plan to use the “Preouts” to feed
a stereo amplifier, you must connect a
stereo signal to the input of the amplifier.
A mono signal into the amplifier will result
in a mono signal out of the preamp output.

10 | JL Audio - XD300/1 Owner’s Manual
SUBWOOFER OUTPUTS
5IF9%JTEFTJHOFEUPEFMJWFSQPXFSJOUP
subwoofer loads equal to or greater than 2 ohms.
5IF9%TTVCXPPGFSPVUQVUTBSF
EFTJHOFEUPBDDFQU"8("8(XJSF5P
connect the subwoofer wires to the amplifier,
first back out the set screws 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.
:PVXJMMOPUJDFUIBUUIFSFBSFUXPi+wQPTJUJWF
DPOOFDUJPOTBOEUXPi–wOFHBUJWFDPOOFDUJPOT
This is to facilitate multiple subwoofer wiring.
The two positive and two negative connections
are connected in parallel inside the amplifier
They are not stereo outputs. Connecting two
subwoofers, each to one set of positive and
negative terminals, will result in a parallel
subwoofer connection. If only connecting one
pair of subwoofer wires, it is not necessary to use
both sets of connections.
IMPORTANT
!
Subwoofer loads below 2 ohms nominal are not
recommended and may cause the amplifier
to initiate a protection mode which reduces
power output.
STATUS LED / PROTECTION CIRCUITRY
5IFSFJTBTJOHMFNVMUJDPMPS-&%POUIFUPQ
surface of the amplifier to indicate the amplifier’s
operating status.
1) Flashing Green: amplifier is powering up,
audio output is muted.
2) Constant Green: amplifier is on and
functioning normally, audio output is active.
3) Constant Red: lights to indicate that the
amplifier has exceeded its safe operating
temperature, putting the amplifier into a
self-protection mode, which reduces the
peak power output of the amplifier. When its
temperature returns to a safe level, the red
light will return to green and the amplifier will
return to full-power operating mode.
4) Constant Amber (yellow): Indicates
that an over-current condition has occurred and
is accompanied by a muting of the amplifier’s
output. Because the muting behavior may be
very short in duration, it may manifest itself as
an audible, repetitive ticking or thumping noise
in the output. Over-current conditions can be
caused by a speaker impedance lower than the
optimum load impedance range for the amplifier
or a short-circuit in the speaker wiring. The
latter can result from a short circuit between the
positive and negative speaker wires or between
either speaker wire and the vehicle chassis.
The “Status LED” will remain amber for a few
seconds, even if the over-current condition is of a
very short duration.
Ò

11
ENGLISH
5) LED off / Amplifier Shuts Off Unexpectedly
The only condition that will shut down
BOVOEBNBHFE9%DPNQMFUFMZJTJGCBUUFSZ
voltage or remote turn-on voltage drops below
WPMUT5IF“Status LED” will turn off when
this occurs. The amplifier will turn back on
when voltage climbs back above 11 volts. If this
is happening in your system, have your charging
system and power wiring inspected.
For more information on troubleshooting this
BNQMJGJFSSFGFSUP"QQFOEJY%QBHFT.
SERVICING YOUR JL AUDIO AMPLIFIER
If your amplifier fails or malfunctions, please
return it to your authorized JL Audio dealer so
that it may be sent in to JL Audio for service.
There are no user serviceable parts or fuses inside
the amplifier. The unique nature of the circuitry
in the JL Audio amplifiers requires specifically
USBJOFETFSWJDFQFSTPOOFM%POPUBUUFNQU
to service the amplifier yourself or through
unauthorized repair facilities. This will not only
void the warranty, but may result in the creation
of more problems within the amplifier.
If you have any questions about the installation or
setup of the amplifier not covered in this manual,
please contact your dealer or technical support.
JL Audio Technical Support:
[phone]
9:00 AM – 5:30 PM (Eastern Time Zone)
Monday - Friday

12 | JL Audio - XD300/1 Owner’s Manual
APPENDIX A:
Input Sensitivity Level Setting
Following the directions below will allow the
installer to adjust the input sensitivity of each
amplifier channel pair simply and easily in just a
few minutes using equipment which is commonly
available in installation bays.
Necessary Equipment
t%JHJUBM"$7PMUNFUFS
t$ %XJUIBTJOFXBWFUFTUUPOFSFDPSEFEBU
E#SFGFSFODFMFWFMJOUIFGSFRVFODZSBOHF
to be amplified for that set of channels
)[GPSTVCXPPGFSDIBOOFMTL)[GPSB
NJESBOHFBQQMJDBUJPO%POPUVTFBUUFOVBUFE
UFTUUPOFTE#E#FUD
The Nine-Step Procedure
1)% JTDPOOFDUUIFTQFBLFSTGSPNUIF
amplifier’s speaker output connectors.
2)
Turn off all processing (bass/treble, loudness,
EQ, etc.) on the source unit, processors (if
used) and amplifier. Set fader control to center
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NBYJNVNJGVTFEUPGFFEUIF9%
3)
Turn the amplifier’s iInput Sens.wcontrol all
the way down.
4)4 FUUIFTPVSDFVOJUWPMVNFUPPGGVMM
volume. This will allow for reasonable gain
overlap with moderate clipping at full volume.
5)
Using the chart on this page, determine the target
voltage for input sensitivity adjustment according
to the nominal impedance of the speaker system
connected to the amplifier outputs.
6)
Verify that you have disconnected the speakers
CFGPSFQSPDFFEJOH1MBZBUSBDLXJUIBO
appropriate sine wave (within the frequency
SBOHFUPCFBNQMJGJFECZUIF9%BU
source unit volume.
7)
Connect the AC voltmeter to the speaker output
connectors of the amplifier. Make sure you test
UIFWPMUBHFBUUIFDPSSFDUDPOOFDUPSTBOEo
8) Increase the iInput Sens.wcontrol until the
target voltage is observed with the voltmeter.
9)0ODFZPVIBWFBEKVTUFEUIF9%UP
its maximum low-distortion output level,
reconnect the speaker(s). The iInput Sens.w
controls can now be adjusted downward if the
amplifier requires attenuation to achieve the
desired system balance.
IMPORTANT
!
Do not increase any iInput Sens.wsetting for
any amplifier channel or channel pair in the
system beyond the maximum level established
during this procedure. Doing so will result in
audible distortion and possible speaker damage.
It will be necessary to re-adjust the
iInput Sens.wif any equalizer boost is activated
after setting the iInput Sens.wwith this
procedure. This applies to any EQ boost circuit,
including source unit tone controls or EQ
circuits. EQ cuts will not require re-adjustment.
Nom. Impedance Target AC Voltage
4 28.3 V
3 27.4 V
2 24.5 V
1 Not Recommended

13
ENGLISH
APPENDIX B:
Precise Frequency Selection Chart
“FILTER FREQ” AMP FILTER
Detent Panel Actual
Number Marking Freq.
Full counter-clockwise: 53
01............................53
02...........“50” ............53
03............................54
04............................54
05............................55
06............................57
07............................59
08...........“60” ............61
09............................63
10............................65
11............................67
12............................70
13............................72
14............................75
15............................78
16...........“80” ............81
17............................85
18............................88
19............................93
20.......“12 o’clock” ........97
21...........................102
22...........................107
23...........................113
24.......... “120” ..........120
25...........................127
26...........................135
27...........................144
28...........................156
29...........................169
30...........................184
31...........................203
32.......... “200” ..........227
33...........................254
34...........................290
35...........................337
36...........................392
37...........................426
38.......... “500” ..........447
39...........................467
Full-clockwise: 470
APPENDIX C:
XD300/1 Specifications
General Specifications:
Recommended Fuse Value: 30A
Recommended Fuse Type: MAXI® or AGU
Input Sections:
No. of Inputs: One Stereo Pair
Input Type: Differential-balanced with RCA jack inputs
Input Range: 100mV - 4V RMS
Amplifier Section:
Amplifier Topology: NexD™ High Speed Class D
Power Supply: Unregulated MOSFET switching type
Rated Power at 14.4V with less than
1% THD+Noise (20Hz - 20 kHz)
200W RMS x 1 @ 4 ohms
300W RMS x 1 @ 2 ohms
Rated Power @ 12.5V with less than
1% THD + Noise (20Hz - 20 kHz)
160W RMS x 1 @ 4 ohms
270W RMS x 1 @ 2 ohms
Signal to Noise Ratio:
>100 dB referred to rated power
(A-weighted, 20 Hz-20 kHz noise bandwidth)
>80 dB referred to 1W
(A-weighted, 20 Hz-20 kHz noise bandwidth)
Frequency Response: 10 Hz - 1 kHz (+0, -1dB)
Damping Factor:
>120 @ 4 ohms / 50 Hz
>60 @ 2 ohms / 50 Hz
Amplifier Filters:
Amplifier Low-Pass Filter:
Sallen-Key, 12 dB/octave Butterworth or 24 dB/octave
Linkwitz-Riley with continuously variable cutoff frequency
selection from 50 - 500 Hz (defeatable).
Preamp Output:
Buffered pass-through type.
Dimensions(LxWxH):
6.85” x 7.09” x 2.05” (174mm x 180mm x 52mm)
Due to ongoing product development, all specifications are subject to
change without notice.

14 | JL Audio - XD300/1 Owner’s Manual
“How do I properly set the input sensitivity on my amplifier?”
Please refer to Appendix A (page 12) to set the input sensitivity for
maximum, low-distortion output.
“My amplifier doesn’t turn on.”
Check the fuse, not just visually, but with a continuity meter. It is
possible for a fuse to have poor internal connections that
cannot be found by visual inspection. It is best to take the
fuse out of the holder for testing. If no problem is found with
the fuse, inspect the fuse-holder.
Check the integrity of the connections made to each of the
i+12VDCwiGroundwBOEiRemotewUFSNJOBMT. Ensure
that no wire insulation is pinched by the terminal set screw
and that each connection is tight.
Check UPNBLFTVSFUIFSFJT7BUUIF “Remote” connection of the
amplifier. In some cases, the turn-on lead from the source unit
is insufficient to turn on multiple devices and the use of a relay
is required. To test for this problem, jump the i+12VDCwwire
to the iRemotewterminal to see if the amplifier turns on.
“I hear a repetitive ticking or popping sound coming out of the speaker(s).”
Check the speaker wires for a possible short, either between the
positive and negative leads or between either speaker lead
and the vehicle’s chassis ground. If a short is present, you will
experience distorted and/or attenuated output. The iStatus
LEDwwill turn amber in this situation. It may be helpful to
disconnect the speaker wires from the amplifier and use a
different set of wires connected to a test speaker.
Check the nominal load impedance to verify that of the amplifier is
driving a load equal to or greater than 2 ohms.
“My amplifier’s output fluctuates when I tap on it or hit a bump.”
Check the connections to the amplifier. Make sure that the
insulation for all wires has been stripped back far enough to
allow a good contact area inside the terminal block.
Check the input connectors to ensure that they all are making good
contact with the input jacks on the amplifier.
APPENDIX D: TROUBLESHOOTING

15
ENGLISH
“My amplifier shuts off once in a while, usually at higher volumes.”
Check your voltage source and grounding point. The power supply
PGUIF9%XJMMPQFSBUFXJUIDIBSHJOHTZTUFNWPMUBHFT
EPXOUP74IVUEPXOQSPCMFNTBUIJHIFSWPMVNFMFWFMT
can occur when the charging system voltage (or remote
UVSOPOWPMUBHFESPQTCFMPX75IFTFEJQTDBOCFPGWFSZ
short duration making them extremely difficult to detect
XJUIBDPNNPO%$WPMUNFUFS5PFOTVSFQSPQFSWPMUBHF
inspect all wiring and termination points. It may also be
necessary to upgrade the ground wire connecting the battery
to the vehicle’s chassis and the power wire connecting the
BMUFSOBUPSUPUIFCBUUFSZ.BOZWFIJDMFTFNQMPZTNBMM
"8("8(XJSFUPHSPVOEUIFCBUUFSZUPUIFWFIJDMFT
chassis and to connect the alternator to the battery. To prevent
voltage drops, these wires should be upgraded to 4 AWG
when installing amplifier systems with main fuse ratings
BCPWF"(SPVOEJOHQSPCMFNTBSFUIFMFBEJOHDBVTFPG
NJTEJBHOPTFEBNQMJGJFSiGBJMVSFTw
“My amplifier turns on, but there is no output.”
Check the input signal using an AC voltmeter to measure the
voltage from the source unit while an appropriate test tone is
played through the source unit (disconnect the input cables
from the amplifier prior to this test). The frequency used
should be in the range that is to be amplified by the amplifier
FYBNQMF)[GPSBTVCCBTTBQQMJDBUJPOPSL)[GPSBGVMM
range / high-pass application). A steady, sufficient voltage
CFUXFFOBOEWPMUTTIPVMECFQSFTFOUBUUIFPVUQVUPG
the signal cables.
Check the output of the amplifier. Using the procedure explained in
the previous check item (after plugging the input cables back
into the amplifier) test for output at the speaker outputs of
the amplifier. Unless you enjoy test tones at high levels, it is
a good idea to remove the speaker wires from the amplifier
while doing this. Turn the volume up approximately half
way. 5V AC or more should be measured at the speaker
outputs. This output level can vary greatly between
amplifiers but it should not be in the millivolt range with
the source unit at half volume. If you are reading sufficient
voltage, check your speaker connections as explained below.
Check to ensure that the speaker wires are making a good
connection with the metal inside the terminal block. The
speaker wire connectors are designed to accept up to 8 AWG
wire. Make sure to strip the wire to allow for a sufficient
connection with the metal inside the terminal block.

16 | JL Audio - XD300/1 Owner’s Manual 17
ENGLISH
INSTALLATION NOTES:
Use this diagram to document your amplifier’s switch and control positions.

LIMITED WARRANTY  AMPLIFIERS USA
+-"6%*0XBSSBOUTUIJTQSPEVDUUPCFGSFFPGEFGFDUTJONBUFSJBMTBOEXPSLNBOTIJQGPSB
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BVUIPSJ[FE+-"VEJPEFBMFSVTJOHB+-"VEJP1SFNJVN1PXFS$POOFDUJPO4ZTUFNGPSQPXFSXJSJOH
This warranty is not transferrable and applies only to the original purchaser from an authorized
+-"6%*0EFBMFS4IPVMETFSWJDFCFOFDFTTBSZVOEFSUIJTXBSSBOUZGPSBOZSFBTPOEVFUPNBOVGBDUVSJOH
EFGFDUPSNBMGVODUJPO+-"6%*0XJMMBUJUTEJTDSFUJPOSFQBJSPSSFQMBDFUIFEFGFDUJWFQSPEVDUXJUIOFX
PSSFNBOVGBDUVSFEQSPEVDUBUOPDIBSHF%BNBHFDBVTFECZUIFGPMMPXJOHJTOPUDPWFSFEVOEFSXBSSBOUZ
accident, misuse, abuse, product modification or neglect, failure to follow installation instructions,
unauthorized repair attempts, misrepresentations by the seller. This warranty does not cover incidental
or consequential damages and does not cover the cost of removing or reinstalling the unit(s). Cosmetic
damage due to accident or normal wear and tear is not covered under warranty.
Warranty is void if the product’s serial number has been removed or defaced.
Any applicable implied warranties are limited in duration to the period of the express warranty as
provided herein beginning with the date of the original purchase at retail, and no warranties, whether
express or implied, shall apply to this product thereafter. Some states do not allow limitations on implied
warranties, therefore these exclusions may not apply to you. This warranty gives you specific legal rights,
and you may also have other rights which vary from state to state.
If you need service on your JL AUDIO product:
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TBMFTSFDFJQU%JSFDUSFUVSOTGSPNDPOTVNFSTPSOPOBVUIPSJ[FEEFBMFSTXJMMCFSFGVTFEVOMFTTTQFDJGJDBMMZ
BVUIPSJ[FECZ+-"6%*0XJUIBWBMJESFUVSOBVUIPSJ[BUJPOOVNCFS
Warranty expiration on products returned without proof of purchase will be determined from the
manufacturing date code. Coverage may be invalidated as this date is previous to purchase date. Non-
defective items received will be returned freight-collect. Customer is responsible for shipping charges and
JOTVSBODFJOTFOEJOHUIFQSPEVDUUP+-"6%*0'SFJHIUEBNBHFPOSFUVSOTJTOPUDPWFSFEVOEFSXBSSBOUZ
For Service Information in the U.S.A. please call
JL Audio Customer Service: [phone]
9:00 AM – 5:30 PM (Eastern Time Zone)
JL Audio, Inc
10369 North Commerce Pkwy.
Miramar, FL 33025
(do not send product for repair to this address)
International Warranties:
Products purchased outside the United States of America are covered only
by that country’s distributor and not by JL Audio, Inc.

Printed in China XD300/1 MAN-08-2010
www.jlaudio.com