JL Audio JX250/1 Manual Del Usuario página 4

remote turn-on
The JX monoblock amplifier is turned on
and off using a conventional +12V remote
turn-on lead, typically controlled by the
source unit's remote turn-on output.
The amplifier will turn on when +12V is
present at its "Remote" input and turn off when
+12V is switched off. If a source unit does not
have a dedicated remote turn-on output, the
amplifier's turn-on lead can be connected to +12V
via a switch that derives power from an ignition-
switched circuit.
18 AWG wire is more than adequate for the
remote turn-on connection. To connect the
remote turn-on wire to the amplifier, strip 1/2-
inch (12 mm) of insulation from the wire and
insert it into the "Remote" receptacle on the
power connector. Tighten the connector down
using the supplied 2.5 mm hex wrench.
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amplIFIer Inputs
The JX monoblock amplifier offers
two input connection methods, one for
high-level (speaker level) signals and one
for low-level (preamp level) signals.
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. For this reason, when feeding a mono
input signal into the "Low-Level Inputs", use a
Y-adaptor splitter to split the mono signal and
connect it to both the Left and Right Low-Level
Inputs of the amplifier.
When feeding a mono signal to the "Hi-Level
Inputs", connect it in parallel to both left and
right input wires.
1) Low-Level Inputs: A standard left/
right pair of RCA type jacks is used for
preamp level (low-level) signal input on
the JX monoblocks. This is the preferred
connection method whenever available.
JL Audio
2) Hi-Level Inputs: If your system does not offer
a preamp level signal option, you can connect
speaker level signals directly to the "Hi-Level
Inputs" connector using the supplied mating
connector and wire harness. Simply splice the
appropriate left/right and positive/negative
wires to the included harness and plug the
harness into the "Hi-Level Inputs" connector
on the amplifier. The JX monoblock will
attenuate the high-level signal to make it
compatible with its input stage.
!
I m p o r ta n t !
Make sure you observe correct polarity in
making the "Hi-Level Input" connections.
Failure to do so will result in a complete loss of
signal (no bass).
The connections for the "Hi-Level Inputs" plug wires
are as follows from left to right on the plug:
White: Left Positive (+)
White/Black: Left Negative (–)
Black: Common Ground (rarely used)*
Gray: Right Positive (+)
Gray/Black: Right Negative (–)
*The only time you will use the "Common
Ground" connection is with some older (pre-
1980's) factory systems or head units that ground
their speakers to chassis ground. To use this
connection, ground the black wire on the plug to
chassis ground and only connect the Left and Right
Positive plug wires to the factory radio outputs.
!
I m p o r ta n t !
If you plan to use the preamp outputs to feed a
stereo amplifier, you must connect stereo
signals to the inputs of the amplifier. A mono
signal into the amplifier will result in a mono
signal out of its preamp output.
JX250/1 • JX500/1D • JX1000/1D
"Input sensItIVItY" (gaIn) adJustment
Located to the left of the input connectors is a
rotary control labeled "Input Sens.". This rotary
control can be used to match the source unit's
output voltage to the input stage of the amplifier
for maximum clean 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, you can then adjust the level of the
amplifier by adjusting the input sensitivity
downward, if the amplifier requires attenuation to
achieve the desired system balance.
Do not increase the "Input Sens." setting for
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.
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