INFINITY KAPPA 4 - TROUBLESHOOTING and CIRCUIT DIAGRAM

Infinity Kappa Four 4 CHANNEL POWER AMPLIFIER _ Schematic _ Troubleshooting _ Exploded view _ Specifications _ Disassembly

SPECIFICATIONS

Output Power: 125W RMS x 4 channels @ 4 ohms; ≤1% THD + N
(14.4V supply) 150W RMS x 4 channels @ 2 ohms; ≤1% THD + N
Total Peak Power 1200W
Signal-to-noise ratio: 85dBA (reference 1W into 4 ohms)
106dBA (reference rated power into 4 ohms)
Frequency response: 10Hz – 75kHz (–3dB)
THD+N 1KHz LPF=22KHz ≤0.05% (rated power @ 4 ohms)
Output Regulation 0.03dB @ 4 ohms
Input Impedance >20K ohms
Maximum input signal: 6.0V
Maximum sensitivity: 200mV
Bass Boost @ 50Hz 0-12dB
Channel Separation ≥50dB
DC Offset <30mV
Idle Current @ 4 ohms 2.0A
Max Current Draw ≤80A
Remote Operating Voltages ON 5V OFF 4V
Turn On Delay Time (sec) 2 - 3
Circuit Protection Temperature (75C), Short circuit, over/under voltage
Operating voltage range (8-16V)
Dimensions: 13"x7"x1.7"(329xmm x179 mm x43.3mm)
Fuses: (2) x 40A

Status LED on Amplifier not Lit - Head Unit (Source) Turned ON
> Remote turn-on wire from source to amplifier has proper voltage
> Power (B+) connections at amplifier, terminal blocks, and battery are secure
> Ground (GND) connections at amplifier and vehicle chassis are secure
> Battery B+ fuse (if used) is OK
> Amplifier fuse is OK
> +B at battery and B+ at amplifier has proper voltage.

Status LED’s Lit, No Output from Speakers in Normal Operating Condition
* RCA cables from amplifier to source are securely connected
* Volume adjustment on amplifier is correctly adjusted
* Source is ON and playing.

Engine Noise From Speaker(s)
> Turn source OFF, Disconnect RCA cables at amplifier. If noise stops, check equipment & cables leading to amplifier.
> RCA cables are of good quality with no breakage to internal shields
> RCA cables from source to amplifier are not run alongside any power cables.

Amplifier Shuts Down, Green LED’s are Lit - Amplifier is in Thermal Protection Mode
> Amplifier is mounted with adequate air circulation around heat sinks or vents
> Amplifier is not mounted under carpet or sealed enclosure
> Speakers meet correct impedance for application (mono or stereo hookup).

Amplifier Output Distorted Music
# Source output music to amplifier is not distorted
# Source output sensitivity is correctly adjusted.

Amplifier Does Not Turn ON, and Red LED is Lit Amplifier (and not Connected to a Shorted Speaker)
> Speaker crossover (if used) is not defective.

EXPLODED VIEW

DISASSEMBLY

1. Remove the two screws at opposite ends on the bottom of the heat sink.
2. Remove the end panel on the Input side only, four Phillips screws.
3. Slide both pieces of silver trim off the heat sink.
4. Remove the top cover; it will be attached with a cable so unplug at Molex connector CN1

5. Remove the Output end panel, five Phillips screws.
6. Remove the terminal screws to the Power connections, and top row only of the speaker terminals.
7. Remove the remaining three Phillips screws on the bottom of the heat sink. There is a nut which may spin on the machine screw; look at the top of the PCB.     
8. Remove all Phillips screws holding the Aluminum transistor clamps on; remove the clamps.
9. Remove the Amplifier PCB; seven Philips screws. The PCB will then pull straight up and off the MAIN PCB.
10. Remove the single Phillips screws holding the 2 terminal temp. Switch in place.
11. Slide the complete PCB out of the heat sink channel.

Access to the output MOSFETS Q2- Q6, Q3A, Q4A, Q5A, Q6A ,Q8-Q14

Follow steps #1-4, and 6, above.
Follow step #8 above to remove the Amplifier PCB
> Remove the gray heat sink from the PCB by grasping and pulling it straight out – it is only held on by friction from the white heat sink compound.
> The (16) output MOSFETS are underneath the rectangular insulator on the PCB.

SCHEMATICS

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