The Kenwood KAC-M1804 is a compact 4-channel car amplifier designed for high-quality audio performance in vehicle sound systems. This Class AB amplifier delivers 45 watts RMS x 4 channels at 4 ohms, features built-in high-pass/low-pass filters, variable bass boost, and speaker-level inputs for easy integration with factory head units. With its compact design and comprehensive protection circuitry, it's ideal for upgrading factory audio systems without requiring extensive modifications.
Key components: Compact chassis design, speaker-level inputs, variable bass boost, high-pass/low-pass filters, protection circuitry.
| Feature | Description |
|---|---|
| Power Output | 45W RMS x 4 channels at 4 ohms |
| Class AB Design | High-quality audio reproduction with low distortion |
| Speaker-Level Inputs | Direct connection to factory head units |
| Variable Bass Boost | Adjustable low-frequency enhancement |
| Crossover Filters | High-pass and low-pass filter controls |
| Compact Size | Easy installation in tight spaces |
| Protection Circuitry | Thermal, overload, and short-circuit protection |
| Power Connection | +12V DC input with fuse protection |
| Remote Turn-on | Remote wire for automatic power control |
| Ground Connection | Secure chassis grounding terminal |
Choose a secure mounting location and prepare all necessary wiring.
WARNING! Disconnect negative battery terminal before installation. Ensure proper fuse rating and secure all connections.
After installation, configure amplifier settings for optimal performance.
CAUTION! Avoid setting gains too high to prevent distortion and speaker damage.
Front panel controls: Input level, bass boost, crossover frequency, filter selection.
Control Functions: Input Level (gain adjustment), Bass Boost (low-frequency enhancement), Crossover Frequency (filter cutoff adjustment), Filter Select (HPF/LPF/Off).
Input Level: Adjust to match head unit output voltage. Bass Boost: Variable control for low-frequency enhancement. Crossover: Adjust cutoff frequency for high-pass or low-pass filtering. Filter Selection: Choose between high-pass, low-pass, or full-range operation.
Speaker-level inputs for factory head units; RCA inputs for aftermarket systems.
Tip: Use appropriate gauge wiring for power and speaker connections.
Normal operation and adjustment procedures.
WARNING! Do not operate with cover removed. Ensure adequate ventilation.
Built-in protection circuits prevent damage from various fault conditions.
| Protection Type | Function |
|---|---|
| Thermal Protection | Shuts down amplifier if overheating detected |
| Overload Protection | Protects against excessive current draw |
| Short-Circuit Protection | Prevents damage from shorted speaker wires |
| DC Offset Protection | Protects speakers from DC voltage |
| Reverse Polarity Protection | Prevents damage from incorrect power connection |
Keep amplifier clean and properly ventilated for optimal performance.
CAUTION! Do not use liquid cleaners. Keep away from moisture and extreme temperatures.
FCC Part 15: Class B digital device compliant. CE marked for European compliance. Copyright © Kenwood Corporation. All trademarks are property of their respective owners. For technical support, visit www.kenwood.com or contact authorized service centers.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| No power | Power connections/fuse | Check +12V, ground, remote connections; verify fuse condition |
| No sound | Input connections/settings | Verify audio input connections; check input level setting |
| Distorted sound | Gain setting/input level | Reduce input level/gain setting; check head unit output |
| Overheating | Ventilation/impedance | Ensure adequate ventilation; verify speaker impedance |
| Protection mode | Short circuit/overload | Check speaker wires for shorts; verify power supply |
Reset: Disconnect power for 30 seconds to reset protection circuits.
Service: Contact authorized Kenwood service centers for repair.