Kenwood MOSFET 50Wx4 Manual

The Kenwood MOSFET 50Wx4 is a high-performance car stereo amplifier featuring MOSFET power supply technology, 50 watts RMS x 4 channels at 4 ohms, low-level RCA inputs, high-level speaker inputs, variable high-pass/low-pass filters, bass boost, and remote turn-on capability. Designed for automotive use with 12V DC power supply. 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 Modes 8. Protection Features 9. Care & Maintenance 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: MOSFET power supply, RCA inputs, speaker terminals, remote turn-on, fuse protection.

Feature	Description
MOSFET Power Supply	High-efficiency switching power supply for clean power delivery
RCA Inputs	Low-level inputs for head unit connection
High-Level Inputs	Speaker-level inputs for factory radio integration
Speaker Terminals	4-channel output for front and rear speakers
Remote Turn-On	Automatic amplifier activation with head unit
Fuse Protection	Internal fuse for over-current protection
Variable Filters	Adjustable high-pass/low-pass crossover networks
Bass Boost	+12dB boost at 45Hz for enhanced bass response
Gain Control	Adjustable input sensitivity matching
Power Indicator	LED shows amplifier operational status

Installation

Unpack and inspect contents. Choose suitable mounting location in vehicle.

Disconnect negative battery terminal before installation.
Mount amplifier: Secure to solid surface using provided hardware.
Connect power: Run 4-gauge power cable from battery positive to amplifier.
Connect ground: Use short 4-gauge cable to clean chassis ground point.
Connect remote: Run remote turn-on wire from head unit to amplifier.
Connect speakers: Use 16-gauge or larger speaker wire to all channels.
Connect RCA cables: Run from head unit outputs to amplifier inputs.

WARNING! Ensure proper fuse rating and secure all connections. Do not run power cables near signal wires.

First-Time Setup

Reconnect battery; power on system for initial configuration.

Set gain controls: Turn all gains to minimum before power on.
Configure input type: Select RCA or high-level input based on head unit.
Set crossover points: Adjust HPF/LPF based on speaker capabilities.
Balance channels: Use test tones to match front/rear output levels.
Fine-tune bass: Adjust bass boost if needed, avoid excessive settings.

CAUTION! Always set gains properly to prevent speaker damage and distortion.

Specifications

Power Output: 50W RMS x 4 channels @ 4 ohms
MOSFET Power Supply: High-efficiency design
Frequency Response: 10Hz - 50kHz (+0/-1dB)
Signal-to-Noise Ratio: >95dB
Input Sensitivity: 200mV - 4V (RCA), 0.5V - 10V (high-level)
Crossover: Variable HPF (50Hz-250Hz), Variable LPF (50Hz-250Hz)
Bass Boost: 0 to +12dB @ 45Hz
Power Supply: 12V DC automotive
Fuse Rating: 25A x 2
Operating Temp: -20°C to +80°C

Controls and Settings

Access controls via front panel knobs and switches.

Front Panel: Power indicator LED, Gain controls (CH1/CH2, CH3/CH4), Bass boost, Crossover frequency, Crossover mode switch (HPF/FLAT/LPF).

Input Selection: RCA or high-level input capability. Gain Control: Adjust input sensitivity for each channel pair. Crossover: High-pass filter for speakers, low-pass filter for subwoofers. Bass Boost: +12dB maximum at 45Hz center frequency. Phase: Normal/reverse phase switching available.

Connecting Devices

RCA inputs: For aftermarket head units. High-level inputs: For factory radios. Speaker outputs: 4-channel connectivity.

Turn off vehicle and disconnect battery before connections.
Match input type to head unit capabilities.
Use proper gauge wiring for power and speakers.
Ensure secure connections at all terminals.
Route cables away from interference sources.

Tip: Use twisted-pair RCA cables to reduce noise interference.

Operation Modes

Supports various audio configurations and crossover settings.

Full-range mode: Set crossover to FLAT for full frequency response.
High-pass mode: Use HPF to protect small speakers from bass frequencies.
Low-pass mode: Use LPF when driving subwoofers.
Bridged mode: Combine channels for higher power output (refer to manual).
Multi-amplifier: Use with additional amplifiers for complete system.

WARNING! Do not bridge channels unless specified in manual. Verify impedance compatibility.

Protection Features

Thermal Protection: Automatic shutdown if overheating detected. Short Circuit Protection: Safeguards against output shorts. DC Offset Protection: Prevents DC voltage at outputs. Over-current Protection: Fuse and electronic current limiting.

Care & Maintenance

Keep amplifier clean and dry. Ensure proper ventilation. Check connections periodically for corrosion or looseness.

CAUTION! Do not block ventilation ports. Avoid water exposure. Disconnect power before cleaning.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. Copyright © Kenwood Corporation; all rights reserved. For support, visit www.kenwood.com or contact authorized Kenwood service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No power	Power/ground connections	Check battery connection; verify ground; inspect fuse.
No sound	Input/RCA connections	Verify RCA cables; check head unit settings; test remote turn-on.
Distorted audio	Gain settings/ground loop	Adjust gain controls; check for proper grounding; inspect speaker connections.
Amplifier protection	Overheating/short circuit	Allow cooling; check speaker wiring for shorts; verify impedance.
Engine noise	Ground loop/poor routing	Improve ground connection; reroute RCA cables away from power wires.

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

Service: Contact authorized Kenwood service center; www.kenwood.com