[. . . ] Repeat for the rear speakers, using the Rear L+ and L­ terminals, and the Rear R+ and R­ terminals. · Four-channel operation: Connect the stereo speakers to the Front terminals, as above. Connect the single speaker into which the amplifier's rear channels will be bridged to the Rear R+ and Rear L­ terminals. [. . . ] Power Input Connectors · +12V: Connect to the positive terminal of the vehicle's battery. Install an appropriate fuse holder and fuse (80A minimum) within 18 inches of the battery. Install protective grommets when routing wires through the firewall or other sheet metal. Refer to the picture below. Factory Bolt Ring Connector Ground Wire Note: Remove any paint below ring connector. Star Washer · REM: Connect to the "Remote Out" lead from the source unit or to a source of switched 12V+ (ACC). Front Input Connectors (RCA) · Connect to the front RCA outputs from the source unit or signal processor. Front Input-Level Control · Used to match the front input level of the amplifier to the output level of the source unit. Front Crossover-Frequency Control · 12dB/octave crossover, variable from 32Hz to 320Hz. Front Crossover-Filter Selector · LPF: Select for subwoofer(s). · Set the Boost control according to your preference, being careful not to apply enough boost to damage your woofer(s). A DBO High-Pass Filter Frequency control, variable between 10Hz and 100Hz. B DBO Boost control provides up to 12dB of boost, slightly above the highpass filter's frequency. Setting Input Level A Turn all Input-Level controls counterclockwise to 6V (minimum). B With a dynamic music track playing, turn the head unit's volume control to the 3/4 position. C Turn Front Input-Level control clockwise until the music is so loud that it no longer sounds clear (distortion is present in the output). D Turn Front-Input-Level control counterclockwise gradually, just until the music sounds clear, once again. F Adjust the Rear and Sub Input-Level controls so that the level of the rear speakers and the level of the subwoofer are proportionate to the level of the front speakers, according to your preference. [. . . ] F Adjust the Rear and Sub Input-Level controls so that the level of the rear speakers and the level of the subwoofer are proportionate to the level of the front speakers, according to your preference. Setting the Crossover A Crossover setting for 5" or larger full-range speakers when no subwoofer is included in the system. B Crossover setting for full-range speakers when a subwoofer is included in the system. [. . . ]