User manual AUDIO DESIGN JX250-1

[. . . ] 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. [. . . ] 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. 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. 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 ignitionswitched circuit. To connect the remote turn-on wire to the amplifier, strip 1/2inch (12 mm) of insulation from the wire and insert it into the "Remote" receptacle on the power connector. Make sure you observe correct polarity in making the "Hi-Level Input" connections. You may run a stereo or a mono signal into the inputs of the amplifier. 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. 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 (pre1980'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. 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 attempt to "bridge" two JX monoblocks together or combine their output to a single load in any manner. 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. SerVIcIng Your 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. 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. [. . . ] Unless you enjoy test tones at high levels, it is a good idea to remove the speaker wires from the amplifier while doing this. 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. [. . . ]