STATUS INDICATOR LIGHTS /
PROTECTION CIRCUITRY
There are three status indicator lights on the top
of the amplifier. These are as follows:
1) “Power” (Green): lights to indicate that the
amplifier is turned on and operating normally.
2) “Thermal” (Red): 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.
3) “Low Ω” (Amber): lights to indicate that the
impedance of the speaker load connected to the
amplifier is lower than the optimum load impedance
range for the amplifier. 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 (this can be a short between the positive and
negative speaker wires or between either speaker
wire and the vehicle chassis).
There is only one condition that will shut
down an undamaged 250/1 completely…
If battery voltage drops below 10 volts, the entire
amplifier will shut itself off.The green “Power”
indicator on the top of the amplifier will turn off
when this occurs.The amplifier will turn back on
when voltage climbs back above 10 volts.This may
happen in a rapid cycle when bass-heavy program
material causes a weak charging system to dip
below 10 volts momentarily. If this is happening in
your system, have your charging system inspected to
make sure it is working properly. A 0.5 or 1.0 Farad
rapid-discharge capacitor connected in parallel to
the amplifier power connections may minimize
these short duration voltage dips in many systems
that are having this problem.
For information on troubleshooting this
amplifier, refer to Appendix D (page 16).
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 trained service personnel. Do not
attempt 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 the
JL AUDIO Technical Department for assistance:
(954) 443-1100
9:00 AM – 5:30 PM Eastern Time,
Monday – Friday
JL AUDIO 250/1 11
on “12dB” and rotate the frequency selection
knob fully clockwise to the “200 Hz” position.This
will activate the “LF Boost” and “Infrasonic Filter”
controls without significantly affecting the crossover
point selected by the external active crossover.
SUBWOOFER OUTPUT
The 250/1 employs JL Audio's exclusive
Regulated, Intelligent Power Supply (R.I.P.S.) design.
This sophisticated power supply allows the amplifier
to produce its optimum power (250 watts x 1)
over a wide range of speaker impedances.
Unlike conventional amplifiers that require a
specific impedance to produce optimum power, the
R.I.P.S.-equipped 250/1 gives you the freedom to
use a variety of subwoofer configurations that
achieve final nominal impedances between
1.5 – 4Ω (without sacrificing power output or
sound quality).
The operation of the R.I.P.S. circuitry is entirely
automatic and adjusts itself every time the amplifier
is turned on according to the lowest impedance
present at the speaker load.There are no user
controls to configure.The system operates through
multiple stages of impedance optimization, choosing
the stage most appropriate to the actual impedance
of the speaker(s) you connect to it.
If you connect a load higher than 4Ω nominal
to the 250/1, power will drop by half with every
doubling of impedance above 4Ω. If you connect a
load lower than 1.5Ω nominal to the 250/1, the
amplifier protection circuitry activates a “safe”
mode which reduces amplifier power to protect
the circuitry from failure (the yellow LED on the
top of the amplifier will light to indicate that this
has happened). See page 11 for details.
Speaker loads below 1.5Ω nominal are not
recommended and may cause the amplifier output
to distort excessively.
Speaker connections to the 250/1 are
straightforward and take place at the far right of the
front panel.You will notice that there are two “+”
positive connections and two “–” negative
connections.This is to facilitate multiple speaker
wiring.The two positive and two negative
connections are connected in parallel inside the
amplifier. Connecting two speakers, each to one set
of positive and negative terminals, will result in a
parallel speaker connection. If only connecting one
pair of speaker wires, it is not necessary to use both
sets of connections.
Do not chassis ground any speakers connected
to this or any other JL Audio amplifier. Doing so will
cause the amplifier to go into protection and mute
the output.
The 250/1's speaker connectors are designed
to accept 12 AWG – 8 AWG wire.
To connect the speaker wires to the amplifier,
first back out the set screws on the top of the
amplifier, using the supplied 2.5 mm hex wrench.
Strip 1/2 inch (12 mm) of insulation from each wire
and insert the bare wire end into the receptacles
on the front panel of the amplifier, seating them
firmly so that no bare wire is exposed.While
holding each wire in place, tighten each 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.
Do NOT attempt to “bridge” two 250/1’s or
combine their output to a single load in any manner.
Doing so will damage the amplifier(s).
Before reconnecting the battery ground and
turning the system on, verify that all control settings
on the amplifier are set according to the needs of
the system.
