Directed Electronics A1200/4 Input Combine, Adjusting Input Gain, High Mass Internal Heatsink

INPUT COMBINE

Your multi-channel amplifier can use both front and rear outputs from your head unit to maintain the ability to fade front to rear, or you can run a single set of RCAs to the front inputs and push in the Rear Input INT/EXT switch on the amplifier endplate to route the front signal to the rear channels as well.

ADJUSTING INPUT GAIN

1.Adjust all amplifier input gain controls to just above minimum sensitivity (fully counterclockwise).

2.Using the cleanest music source (CD) playing, turn up the head unit source volume until you can hear distortion. Now turn it down a bit until you cannot hear the distortion (usually just below full volume).

3.Increase the amplifier gain (clockwise) until the onset of audible distortion. Then decrease the gain to the point just before the distortion starts. This setting minimizes background noise and prevents overload.

4.Repeat step 3 for any remaining independently controlled amplifiers (rear and subwoofer gain controls) in the system.

HIGH MASS INTERNAL HEATSINK

The unique heatsink on your amplifier has been designed with fins on the inside of the aluminum extrusion. This allows for the transfer of heat from the circuitry to the heatsink fins and out through the vents in the endplates. Be sure you provide ample space around the amplifier for cooling: at least 2” on all sides.

AP-IV PROTECTION CIRCUIT

Short Circuit Protection engaged: These amplifiers will turn off and try to come back on immediately (the status LEDs will flash). The amplifier will cycle like this indefinitely with “blips” of sound each time. If this is the case, check your speakers and wiring for low impedance and short circuits.

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