User manual BOSTON ACOUSTICS GT42

[. . . ] Do not connect 12V accessories to this input. 9 REAR Input Switch In the left position, the L & R inputs go to the REAR L & R channels of the amplifier. Use this setting when the REAR channels are used with a subwoofer. 10 Lowpass Slope and Crossover Controls OFF L OWPASS ON Select appropriate crossover slope of 12 or 24dB/octave by moving LOWPASS SLOPE switch. Lowpass crossover frequencies are adjustable from 50Hz to 350Hz by rotary control. Move filter switch to "ON" position to engage. L OW PA SS SL O PE 12d B 12d B 24d B M ON O ST 200 350 Hz 50 11 Status LED Indicators GREEN indicates the normal operating condition; the amplifier is "ON. " GREEN and RED together are normal when the amplifier is first turned "ON"; RED will turn off after a few seconds. [. . . ] If other devices are connected to this wire, the fuse value should be of sufficient capacity to handle the demand. FUSE 3 x 20A Wire Gauge The amplifier accepts up to 4-gauge stripped wire at the DC power and ground input terminals, and 4-gauge is recommended. Wire runs should be kept to the minimum practical length. 10 Installation--Fuses and Wiring (cont. ) Power/B+ and Power/GND Connection Strip approximately 5/8" (16mm) of insulation. The positive (+) power wire is installed into the amplifier terminal marked "B+. " The negative (­) wire is installed into the terminal marked "GND. " The ground wire should be as short as possible and connected directly to the chassis of the vehicle. Make sure that the chassis connection point is free of rust, grease, dirt, paint, and other materials that may insulate the ground wire from making proper connection. Tighten the B+ and GND terminals with the supplied 3mm hex wrench to secure the wire into the terminals. If the power wire must be routed through a drilled or existing hole, use a nylon panel grommet to prevent fraying the wire insulation. Failure to do so could lead to an electrical short if the wire insulation is worn through and the power wire is shorted to ground. 1/ " 4 Strip 5/8" (16mm) Remote Input Connection Use the supplied FEMALE slide connector to connect the REMOTE trigger lead from the head unit to the amplifier. Crimp connector to wire from head unit that controls remote turn-on (refer to head unit owner's manual). Once the slide connector is crimped into place, carefully push connector onto recessed male REMOTE terminal adjacent to the RCA Input pair. If the head unit has any equalization or bass management features such as boost, they should be defeated at this time. Turn head unit on, and verify that the GREEN status LED is lit on the amplifier. 5) Volume With the chosen musical track playing, turn the head unit volume control up until the maximum level of undistorted signal is heard from the speakers. (For most head units, this will be near the end of the volume control range. ) WARNING!A distorted signal from the head unit sent to the amplifier can cause loudspeaker failure at higher listening levels! 6) FRONT Input Sensitivity Control Slowly rotate control clockwise until maximum undistorted playing level is heard from the speakers. If detected, rotate FRONT Input Sensitivity counterclockwise until it is eliminated. 7) FRONT Crossover Controls To achieve higher undistorted playing levels from the front speakers, the FRONT crossover must be engaged. Move crossover switch to the right (ON) position. OFF H I G H PA S S ON 350 Slowly rotate FRONT input sensitivity control clockwise until maximum undis185 Hz torted playing level is heard from the speakers. If detected, rotate FRONT input sensitivity control counterclockwise until it is eliminated. Slowly rotate FRONT highpass crossover control counterclockwise while listening for bottoming. You are lowering the crossover point, which means that more bass signal is being sent to the speakers. If bottoming is detected, Rotate FRONT input sensitivity control counterclockwise until it is eliminated and/or rotate the FRONT highpass crossover control clockwise to raise the crossover point. 13 Setup Tuning--Full-Range Speakers (cont. ) 8) FRONT "Q" Control Once the FRONT highpass crossover point has been determined, use the FRONT "Q" control to increase the bass information centered around the crossover point. Setting the front "Q" control is done in conjunction with setting the levels on the input sensitivity and highpass crossover frequency controls. You may find while setting the "Q" that bottoming may be detected in the front speakers; lowering the "Q" input sensitivity or raising the highpass crossover point will eliminate this. Minor adjustments to each setting are required to fine-tune the system. [. . . ] Your responsibilities are to use the system according to the instructions supplied, to provide safe and secure transportation to an authorized Boston Acoustics service representative, and to present proof of purchase in the form of your sales slip when requesting service. Excluded from this warranty is damage that results from abuse, misuse, accidents, shipping, or repairs or modifications by anyone other than an authorized Boston Acoustics service representative. This warranty is void if the serial number has been removed or defaced. This warranty gives you specific legal rights, and you may also have other rights that vary from state to state. If Service Seems Necessary First, contact the dealer from whom you purchased the amplifier. [. . . ]