User manual INFINITY REFERENCE 311A 611A 1211A 7521A 7541A 5761A

[. . . ] · Turn off the audio system and other electrical devices before you start. Disconnect the (­) negative lead from your vehicle's battery. · Check clearances on both sides of a planned mounting surface before drilling any holes or installing any screws. · At the installation sites, locate and make a note of all fuel lines, hydraulic brake lines, vacuum lines and electrical wiring. [. . . ] Speaker-level connector. HIGH-LEVEL INPUT + R ­ + L ­ GRAY + ­ WHITE/BLACK + WHITE Figure 1. Terminal-connection end plate. GRAY/BLACK ­ LR Speaker Wires (spliced) 2 APPLICATIONS ­ 311a, 611a AND 1211a The Reference subwoofer amplifiers are single-channel amplifiers. There are two sets of terminals to make it easy to connect multiple woofers. Either set of (+/­) terminals may be used when connecting woofers. To the right are two application diagrams to help plan your subwoofer system installation. Figures 3 and 4 show how to configure the Reference subwoofer amplifiers (models 311a, 611a and 1211a). NOTE: For simplicity, Figures 3 and 4 do not show power, remote and input connections. Reference subwoofer amplifier with two woofer connections. Figure 4. Reference subwoofer amplifier with one woofer connection. APPLICATIONS ­ 7521a The 7521a amplifier can be set up for stereo or bridged-mono operation, as shown in Figures 5 and 6. NOTE: For simplicity, Figures 5 and 6 do not show power, remote and input connections. Minimum speaker impedance for bridged operation is 4 ohms. Figure 5. 7521a amplifier set up for bridged-mono operation. 3 APPLICATIONS ­ 7541a The 7541a can be set up for stereo 4-channel, 3-channel or bridged 2-channel operation, as shown in Figures 7 through 9. NOTE: For simplicity, Figures 7 through 9 do not show power, remote and input connections. 7541a amplifier in 4-channel (stereo) operation to drive front and rear full-range speakers. Figure 8. 7541a is set up for 3-channel operation to drive a set of full-range speakers and a subwoofer. 4 Figure 9. 7541a used in bridged 2-channel mode to drive a set of components or subwoofers. APPLICATIONS ­ 5761a The 5761a can be configured for 6-channel, 5-channel or 3-channel operation, as shown in Figures 10 through 12. INPUT MODE SWITCH: · Use INT (internal mode) to send a signal from the front and rear inputs to the subwoofer. · Use EXT (external mode) when sending a dedicated signal to the subwoofer inputs; e. g. , if your source unit has a subwoofer output. NOTE: For simplicity, Figures 10 through 12 do not show power, remote and input connections. Minimum speaker impedance for bridged operation is 4 ohms. Figure 10. 6-Channel operation: 5761a amplifier driving full-range front and rear speakers and a pair of subwoofers. Figure 11. 5-Channel operation: The same as Figure 10, with the subwoofer output bridged to drive a single 4-ohm subwoofer, providing the speaker with more power. Figure 12. 3-Channel operation: 5761a amplifier configured for 3-channel operation, where all of the channels are bridged for a subwoofer and a pair of component speakers. 5 INSTALLATION AND SETUP SETTING THE CROSSOVER(S) Determine your system plans and set the crossover-mode switch accordingly. [. . . ] The DBO allows you to adjust the frequency (20Hz ­ 80Hz) as well as the boost level (up to 12dB; see Figure 14), allowing you to fine-tune the bass in your system to optimize performance. For sealed enclosures, the DBO can be used to enhance the lower bass region of sealed enclosures. For bigger/fuller bass, adjust the HP FREQ between 35Hz and 45Hz; adjust the BOOST control according to your preference. For tighter-sounding bass, adjust the HP FREQ between 45Hz and 55Hz; adjust the BOOST control according to your preference. [. . . ]