User manual JBL GTQ100

[. . . ] Skill with tools, an understanding of basic electronics, and experience with car stereo installation are needed to properly install this amplifier. If you feel you do not have the necessary knowledge and skills, we strongly recommend that the installation be done by your authorized JBL dealer. If the GTQ amplifier is installed by an authorized JBL dealer in the USA, we will double the length of your warranty to two years from date of purchase. Please retain a copy of your bill of sale to ensure this additional coverage. [. . . ] · The proper speaker connection depends on whether a group of the GTQ amplifier is used bridged or stereo. In either configuration the speakers are connected to the speaker output connector. · To get proper bass response and stereo imaging, all the speakers in the system must be in phase. The input terminals of the speakers will be marked in some way to identify positive and negative polarity. Make sure that the positive (+) speaker terminal is attached to the positive (+) amplifier connection in every speaker-toamp connection. All two-conductor speaker wire has one conductor marked in some way so it can be easily traced. · Stereo Connection ­ Connect each speaker to appropriately labeled terminals of the speaker output connector. · Bridged-Mode Connection ­ Connect the loudspeaker positive (+) terminal to the RIGHT positive amplifier speaker output terminal on the group to be bridged. Connect the loudspeaker negative (­) terminal to the LEFT negative amplifier speaker output terminal on the group to be bridged. The appropriate group mode switch should be set to LEFT or L+R. 08 GTQ 190 - English 06/03/98 11:49 Side 9 )­( )+( GR1 L LINE LEVEL INPUT GR2 PREAMP OUTPUTS GR1 GR2 SPEAKER LEVEL INPUTS R GR2 L +­ ­+ GR2 + R SPEAKER OUTPUTS BRIDGE ­ +L ­ FUSE 30A POWER R +­ ­+ R GR1 L GR1 + R ­ + L ­ BATT(+) REMOTE BRIDGE GND Audio Input Connections Line-Level Input Connections · Proper wiring between the signal source, any other components in the system, and the GTQ amplifier will help keep noise levels in the system low. Use high-quality, twisted-pair cable or lowcapacitance shielded wire. )+( )­( )+( )­( Simultaneous Stereo-Mono Connection Diagrams 09 Owner's Manual · Simultaneous Stereo + Mono Connection­ Each of the two groups of the GTQ amplifier may be used to drive a stereo pair of speakers with a mono speaker at the same time. When using two head units, both the speaker and preamp-level inputs may be used simultaneously. Be sure to maintain left and right channel consistency. · Bridged Mode Operation ­ To select bridge mode operation, set the mode switch for the appropriate group in either the L only or L+R position. In the L position, signal from the left input is fed to both left and right amplifier outputs for that group. In the L+R position, the signal from both the left and right inputs is summed internally. When using a group of the GTQ amplifier for mono mode fed with a stereo signal it is best to use the L+R mode. When feeding a single GTQ amplifier channel group with a mono signal from an outboard crossover, use the L mode and connect your source input to the left input of the desired group to be used in bridged mono. · Simultaneous Stereo + Mono ­ Set the Mode switch for the appropriate group to the stereo position. Main speakers are connected normally to the left and right stereo outputs of the group, and a center speaker or subwoofer speaker is connected to the same group as in bridged mode. Refer to the diagram on page 9 for connection details. Speaker-Level Input Connections When speaker-level signal is used to drive the GTQ amplifier, the signal goes into the amp through a special eight-wire harness/connector (see the "Controls and Connectors" section). If extension wires are needed between the head unit output and the amplifier unit, use conventional speaker wire or twisted-pair wiring. [. . . ] When power and signal leads must cross, they should cross at right angles. If you suspect that power line noise is being induced in the signal leads, you can repeat the test for source noise described previously, but perform the test at the amplifier end of the signal cables. One power wire that will be impossible to stay away from is the vehicle chassis. Use high-quality shielded cables, twisted pair, or a balanced-line system for the long front-to-rear signal runs to reduce the likelihood of noise pickup from this source. [. . . ]