Kenwood KAC 6485 Manual

The Kenwood KAC 6485 is a 4-channel car amplifier delivering 45 watts RMS x 4 channels at 4 ohms or 60 watts RMS x 4 channels at 2 ohms. Features include MOSFET power supply, variable high-pass/low-pass filters, bass boost, speaker-level inputs, preamp outputs, and protection circuits. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Devices 7. Operation Guidelines 8. Protection Features 9. Care & Maintenance 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: MOSFET power supply, 4-channel amplification, variable filters, bass boost control, speaker-level inputs.

Feature	Description
Power Output	45W x 4 (4Ω), 60W x 4 (2Ω)
MOSFET Power Supply	Efficient and reliable power delivery
Variable HP/LP Filters	Adjustable high-pass and low-pass filters
Bass Boost	+12dB boost at 50Hz
Speaker-Level Inputs	Connect directly to factory head units
Preamp Outputs	Daisy-chain multiple amplifiers
Protection Circuit	Thermal, overload, and short circuit protection
Bridgeable	Can be bridged for 2-channel operation
Signal-to-Noise Ratio	>100dB
THD	<0.08%

Installation

Choose proper mounting location and prepare wiring.

Select mounting location: Dry, well-ventilated area away from heat sources.
Power connections: Connect +12V to battery, ground to chassis, remote turn-on to head unit.
Speaker connections: Connect speakers to appropriate channels observing polarity.
Input connections: Use RCA inputs or speaker-level inputs as needed.
Fuse installation: Install appropriate fuse near battery connection.

WARNING! Disconnect battery before installation. Ensure proper ventilation for cooling.

First-Time Setup

Configure amplifier settings for optimal performance.

Gain adjustment: Set gain control to match head unit output level.
Filter selection: Choose high-pass or low-pass filter based on speaker application.
Frequency adjustment: Set crossover frequency appropriate for speakers.
Bass boost: Adjust if needed, but use sparingly to avoid distortion.
Test operation: Verify all channels working properly.

CAUTION! Start with conservative settings and adjust gradually. Avoid clipping.

Specifications

Channels: 4
RMS Power: 45W x 4 @ 4Ω, 60W x 4 @ 2Ω
Bridged Power: 120W x 2 @ 4Ω
Frequency Response: 10Hz - 50kHz
Signal-to-Noise Ratio: >100dB
THD: <0.08%
Crossover: Variable HP/LP (50Hz - 200Hz)
Bass Boost: +12dB @ 50Hz
Input Sensitivity: 0.2V - 4V
Fuse Rating: 25A x 2

Controls and Settings

Front panel controls and adjustment points.

Controls: Power indicator, Protection indicator.

Adjustment Points: Input level/gain control, HP/LP filter selector, Frequency control, Bass boost control. Input selector (RCA/Speaker level).

Setup: Gain adjustment (match to head unit), Filter selection (HP for highs, LP for subs), Frequency setting (50-200Hz range), Bass boost (0-12dB).

Connecting Devices

RCA inputs: For aftermarket head units. Speaker-level inputs: For factory head units. Preamp outputs: For daisy-chaining amplifiers.

Disconnect vehicle battery before making connections.
Use proper gauge wiring for power and ground.
Route signal cables away from power wires to avoid noise.
Secure all connections and test before final installation.

Tip: Use crimp connectors and heat shrink for reliable connections.

Operation Guidelines

Proper operation for optimal performance and longevity.

Power sequence: Turn on head unit first, then amplifier.
Volume control: Increase volume gradually to avoid clipping.
Thermal management: Ensure adequate ventilation during operation.
Load impedance: Do not connect speakers below minimum impedance rating.
Bridge mode: Use appropriate wiring when bridging channels.

WARNING! Do not operate with impedance below specified minimum. Avoid excessive gain settings.

Protection Features

Thermal Protection: Automatically reduces output if overheating detected. Overload Protection: Protects against excessive current draw. Short Circuit Protection: Safeguards against speaker wire shorts. DC Offset Protection: Prevents DC voltage from reaching speakers.

Care & Maintenance

Keep amplifier clean and dry. Periodically check connections for corrosion or looseness.

CAUTION! Do not use chemical cleaners. Keep ventilation ports clear of obstructions.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits. CE compliant for European markets. Copyright © Kenwood Corporation. For support, visit www.kenwood.com or contact authorized Kenwood service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No power	Power connections	Check battery, ground, and remote connections; verify fuse condition.
Protection mode active	Overheating/short circuit	Allow to cool; check speaker wires for shorts; verify impedance.
No sound from channels	Input/connection issues	Check RCA cables; verify input selector setting; test head unit output.
Distorted sound	Gain/clipping	Reduce gain setting; check head unit volume; verify speaker condition.
Amplifier overheating	Ventilation/load	Improve ventilation; check impedance load; reduce bass boost.

Reset: Disconnect power for 30 seconds to reset protection circuits.

Service: Contact authorized Kenwood service center for repairs.