“REMote” turn-On
The J2-500.1 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 a Phillips screwdriver.
“AMPLIFIER InputS”
The J2-500.1 only offers low-level (preamp level) input connections via a single pair of RCA- type jacks that are compatible with a wide range of aftermarket source units and processors. If you wish to use speaker level signals, you will need to employ a line-output converter (not included).
mp Amplifier
uts Inputs
TLEFT
Rev
Ou
TRIGHT
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 into the RCA jacks, we recommend that you use a “Y-adaptor”to split the mono signal into both the Left and Right inputs of the amplifier.
If you plan to use the preamp outputs 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.
“INPUT SENSITIVITY” (GAIN) ADJUSTMENT Located next to 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.
wer
min max | 40 |
Input Sens. | LP Filter Fr |
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.
“LP FILTER” (CroSSOVER) Control
The J2-500.1 employs a 12dB/octave low-pass (LP) active filter for its internal channel. This feature is designed to attenuate frequencies above its filter frequency, so that the system’s subwoofers do not reproduce any audible midrange content.
The low-pass filter in the J2-500.1 is fully variable between 40 Hz and 130 Hz via the “LP Filter Frequency” control knob. The 12 o’clock position corresponds to 80 Hz, and is a good starting point for system tuning.
40 130
LP Filter Frequency (Hz)
“Output Polarity” CONTROL
The J2-500.1 includes a switch to quickly reverse the polarity of its audio output. This is very useful for establishing a smooth transition between the subwoofers and main speaker systems. Choose the position that results in the strongest midbass and the best “up-front” bass presence.
r
Pow
Reversed Normal
Output Polarity
