Target Audience:
Professional car audio installers, repair shops, and advanced DIY car audio enthusiasts seeking to service or repair Kenwood KAC-927 and KAC-PS300 amplifiers.
Original Price Point:
Mid-range to high-end aftermarket car amplifiers in their original release.
Value Proposition:
Provides essential technical data and diagnostic procedures typically unavailable in owner's manuals, enabling cost-effective repair and maintenance of high-performance amplifiers.
Diagnostic Capability:
Enables precise identification and rectification of audio signal path issues, power delivery problems, and protection circuit faults.
Repair Efficiency:
Streamlines the repair process by offering clear schematics, component identification, and systematic troubleshooting steps.
Models Covered:
Kenwood KAC-927, Kenwood KAC-PS300
Model Variants:
Covers standard configurations and potential variations within the KAC-927 and KAC-PS300 product lines.
Page Count:
Estimated 50-75 pages (typical for this type of component service manual)
Manual Type:
Service Manual
Language:
English (typical for Kenwood service documentation)
Power Supply Circuitry:
Detailed schematics and troubleshooting for power regulation and protection circuits.
Audio Pre-Amplifier Stage:
Explanation of signal path, component functions, and adjustment procedures for the input and gain stages.
Power Amplifier Stage:
In-depth coverage of output transistor biasing, thermal management, and waveform analysis.
Protection Circuitry:
Diagnosis and repair of DC offset, overload, and thermal protection mechanisms.
Input Output Connections:
Wiring diagrams and specifications for RCA inputs, speaker outputs, and remote turn-on terminals.
Internal Pcb Layout:
Layout diagrams of the Printed Circuit Board for component identification and desoldering/soldering.
Control Circuitry:
Analysis of front panel controls (gain, filters) and their associated circuitry.
Troubleshooting Guides:
Step-by-step diagnostic procedures for common and uncommon audio malfunctions.
Component Level Repair:
Identification and replacement procedures for key electronic components (transistors, ICs, capacitors).
Alignment And Calibration:
Procedures for setting DC offset, gain structure, and thermal tracking if applicable.
Schematic Diagrams:
Detailed electronic schematics for complete circuit analysis and understanding.
Exploded Views:
Illustrations showing internal component layout and disassembly procedures.
Wiring Diagrams:
Detailed wiring harness diagrams for connecting power, ground, remote, and speaker outputs.
Voltage Measurements:
Specification of critical test points and expected voltage readings for diagnostic purposes.
Depth Of Coverage:
Component-level troubleshooting and repair, suitable for experienced audio technicians and advanced DIY enthusiasts.
Diagnostic Tools Required:
Oscilloscope, multimeter, signal generator, soldering station, component tester.
Schematic Annotations:
Component designators, part numbers (where applicable), voltage levels, and signal flow annotations on schematics.
File Format:
High-resolution PDF
Searchability:
Likely includes searchable text for quick access to specific components or sections.
Print Quality:
Printable for physical reference, high clarity for schematics and diagrams.
Binding Type:
N/A (Digital PDF download)
Paper Type:
N/A (Digital PDF download)
Amplifier Type:
Class AB (typical for KAC-927), likely Class D for KAC-PS300, or Class AB depending on specific PS300 variant.
Kac 927 Power Output:
2-Channel: 150W x 2 (4 Ohms), 250W x 2 (2 Ohms), 500W x 1 (Bridged, 4 Ohms)
Kac Ps300 Power Output:
Refer to specific KAC-PS300 variant; typically a 4-channel amplifier (e.g., 50W x 4 @ 4 Ohms).
Frequency Response:
20 Hz - 20 kHz
Signal To Noise Ratio:
Typically > 95 dB
Total Harmonic Distortion:
Typically < 0.05% THD
Damping Factor:
Refer to specific model, but generally >100 for Kenwood amplifiers of this era.
Power Requirements:
11-16 VDC, Negative Ground
Overload Protection:
Thermal, DC offset, and speaker short circuit protection circuits are detailed.
Turn On Delay:
Soft turn-on circuitry to prevent speaker thump is covered.
Heat Dissipation:
Internal heatsink design and thermal management considerations are discussed.
Preamp Level Inputs:
RCA inputs for connecting to head unit preamp outputs.
N A:
N/A for amplifier service manual.
Speaker Outputs:
Screw terminals for speaker connections.
Remote Turn On:
Terminal for receiving turn-on signal from head unit.
Input Sensitivity Adjustment:
Covers adjustment of input gain controls for optimal signal matching.
Preventative Maintenance:
Not applicable for component-level service manuals; maintenance focuses on repair and troubleshooting.
Thermal Paste:
Specification and application of thermal paste for power transistors and heatsinks is a critical repair step covered.
Common Failures:
Output stage failure (blown transistors), power supply regulation issues, faulty protection circuits, and intermittent connections.
Troubleshooting Focus:
Diagnosis of audio clipping, lack of output, popping noises, and amplifier shutting down prematurely.
Speaker Terminal Wear:
While not directly in the manual, proper torque and connection maintenance for speaker terminals is implied for preventing faults.
Kenwood Audio Legacy:
Kenwood is a long-standing and reputable brand in the automotive audio industry, known for producing reliable and high-performance car audio components since the 1960s.
Amplifier Lineup:
The KAC series amplifiers were popular for their power, sound quality, and features in their production era, often paired with Kenwood head units and speakers.
Production Era:
These models were typically produced in the late 1990s to early 2000s, a period of significant advancement in car audio technology.
