INFINITY KAPPA202A
Service Manual

Kappa 202a

INSTALLATION (continued)
3. Make sure the wires are firmly seated in each Weco 2-pin connector and that each screw is completely tightened. Insert the wired connectors into the POWER sockets on the amplifier. Press each one in until it stops. 4. Using the Weco 5-pin connector, connect a blue wire from the source unit�s remote connection to the REM terminal. Depending on polarity requirements (e.g., bridged-mono or tri-mode configurations � see Figures 1 through 3 on page 3), connect speaker wires from the speakers to the L and R (+ and �) terminals, as required by your system plan. 5. Make sure the wires are firmly seated in the Weco 5-pin connector and that each screw is completely tightened. Insert the wired Weco 5-pin connector into the 5-pin socket on the amplifier. Press it in until it stops. 6. Connect RCA cables from a source unit to the L and R INPUT jacks.

SETTING INPUT SENSITIVITY...
Initially, turn the input sensitivity GAIN control to its minimum (counter-clockwise) position (refer to Figure 8). 1. Reconnect the (�) negative lead to your vehicle�s battery. Apply power to the audio system and play a favorite music track from CD or tape.
NOTE: After the source unit is on, green LEDs (on the top pane)l will illuminate, indicating the amplifier is on. If not, check the wiring, especially the remote connection from the source unit. Also refer to �Troubleshooting� on the next page.

2. On the source unit, increase the volume control to maximum position. Slowly increase the GAIN control (clockwise) towards three o� clock and, at the same time, listen to the quality of the reproduced sound. At some point, you�ll hear distortion on the music peaks. Stop the adjustment and turn it back slightly.

SETTING THE CROSSOVER...
IMPORTANT: If you plan to use the Kappa 202a to drive full-range speakers, set both AMP and AUX filters to FLAT (refer to Figure 1 on page 3 and Figure 8 below) and skip to the next section, �Setting Input Sensitivity�.

SETTING DBO...
Dynamic Bass Optimizer (DBO) is a new approach to enhancing low-frequency reproduction in a vehicle. Conventional bass boost controls add bass at a fixed frequency and cause the amplifier to consume considerable power. DBO conserves valuable power at the lowest frequencies and allows you to adjust the level and �character� of the bass sound, instead of just the amount of boom. Since a subwoofer in a tuned box is given to overexcursion below the tuned frequency, set the FREQ control below the box�s resonant (tuned) frequency (see Figure 9 on the next page). Power typically wasted in this region will now be conserved and instead be available for frequencies the enclosure will reproduce. Use the Q control to boost the bass at the set frequency by as much as 12 dB (at MAX position � see Figure 9 on the next page). For sealed enclosures, use DBO to enhance the output so it sounds more like a tuned box. This is a result of 12 dB of rolloff being added to the enclosure�s rolloff and a flattening of frequency response (at the curve�s knee) when Q is boosted. For infinite baffles, set the FREQ control to the speaker�s Fs value (to keep the subwoofer from trying to create bass below the resonant frequency) and adjust the Q control according to personal taste.

1. Set the CROSSOVER control to the frequency recommended by speaker manufacturer (refer to Figure 8). If the value is unknown, set the control midway.

INSTALLING THE CONTROL COVER...
Figure 8. Kappa 202a controls for crossover, input, output, and DBO (Dynamic Bass Optimizer).

After wiring and testing the Kappa 202a amplifier, install the control cover using the enclosed machine screws to deter tampering and help seal out dust.
NOTE: Do not over-tighten the machine screws. Doing so may crack the cover.

2. Depending on your system plan, set the AMP and AUX switches to LP (low-pass), HP (high-pass), or FLAT (refer to Figure 8).

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