Audio Equipment Repair Course

Lesson 1 • Reading Audio Schematics

Teaches standard schematic symbols and signal-flow conventions used in audio equipment documentation. Enables accurate circuit tracing before physical inspection.

Lesson 2 • Electrical Fundamentals for Audio

Covers voltage, current, resistance, and power as applied to audio circuits. Establishes the quantitative baseline needed for all subsequent diagnostic work.

Lesson 3 • Test Equipment Essentials

Introduces multimeters, oscilloscopes, and signal generators as primary diagnostic tools. Proper use of each instrument is tied directly to audio fault-finding tasks.

Lesson 4 • Workshop Safety and Organization

Establishes ESD precautions, electrical safety rules, and bench organization standards. Safe habits prevent equipment damage and personal injury throughout the course.

Lesson 1 • Power Supply Fundamentals

Explains rectification, filtering, and regulation as applied to audio power supplies. Power supply faults are among the most common causes of audio equipment failure.

Lesson 2 • Amplifier Topologies

Examines Class A, AB, B, and D amplifier designs and their trade-offs. Each topology produces distinct failure signatures that technicians must recognize.

Lesson 3 • Digital Audio Interfaces

Introduces ADC, DAC, and common digital audio formats found in modern equipment. Provides context for diagnosing hybrid analog-digital signal paths.

Lesson 4 • Preamplifier and Tone Control Circuits

Covers op-amp-based preamp stages, tone stacks, and equalization networks. These circuits appear in nearly every piece of audio equipment.

Lesson 1 • Surface-Mount Soldering and Rework

Introduces SMD hand-soldering, hot-air rework, and paste application for modern audio boards. SMD skills are increasingly required as equipment miniaturizes.

Lesson 2 • Soldering Station Setup and Tools

Covers iron selection, tip maintenance, temperature control, and flux types. Proper setup is the prerequisite for consistent, high-quality solder joints.

Lesson 3 • Post-Repair Inspection and Cleaning

Establishes standards for flux residue removal, visual inspection, and electrical verification after soldering. Clean, inspected boards prevent latent failures.

Lesson 4 • Through-Hole Soldering Techniques

Teaches correct joint formation, heat application, and inspection for through-hole components. These skills apply to the majority of vintage and mid-range audio equipment.

Lesson 1 • Signal Injection and Tracing

Teaches injecting test tones and tracing them stage by stage to locate signal loss or distortion. This technique pinpoints the faulty stage before component-level testing.

Lesson 2 • Component-Level Testing Techniques

Covers in-circuit and out-of-circuit testing of resistors, capacitors, transistors, and ICs. Accurate component testing prevents unnecessary replacements.

Lesson 3 • Systematic Troubleshooting Methodology

Introduces a structured fault-finding process: observe, hypothesize, test, and verify. A repeatable method reduces diagnostic time and prevents misdiagnosis.

Lesson 4 • Power Supply Diagnostics

Focuses on diagnosing rectifier failures, regulator dropout, and filter capacitor degradation. Power supply faults often mimic other failures and must be ruled out first.

Lesson 1 • Protection and Relay Circuits

Explains speaker protection relays, DC offset detectors, and thermal shutdown circuits. Restoring protection circuits is mandatory before returning equipment to service.

Lesson 2 • Output Stage Repair Procedures

Guides replacement of output transistors, matched pairs, and associated resistors. Correct matching and biasing after replacement ensures reliable long-term operation.

Lesson 3 • Common Amplifier Failure Modes

Catalogs the most frequent amplifier faults: blown output transistors, failed bias circuits, and shorted rails. Pattern recognition accelerates diagnosis on the bench.

Lesson 4 • Preamplifier and Op-Amp Repair

Addresses op-amp substitution, gain stage faults, and tone control failures in preamp circuits. Preamp repairs require careful attention to noise and offset specifications.

Lesson 1 • Channel Strip Fault Diagnosis

Covers dead channels, noise, distortion, and phantom power failures in mixer channel strips. Channel strip faults are the most common mixer repair category.

Lesson 2 • Dynamics Processor Repair

Covers compressor, limiter, and gate circuit faults including VCA failures and sidechain issues. Dynamics processors require functional testing under signal conditions.

Lesson 3 • Mixer Architecture and Signal Routing

Maps the channel strip, bus routing, and master section of analog mixing consoles. Understanding routing is essential before tracing faults in complex multi-channel boards.

Lesson 4 • Equalizer and Filter Repair

Addresses parametric and graphic EQ faults including broken frequency controls and op-amp failures. EQ circuits share topology with preamps, reinforcing earlier skills.

Lesson 1 • Speaker Diagnostic Procedures

Covers DC resistance, impedance sweep, and listening tests to classify speaker faults. Accurate diagnosis prevents unnecessary reconing of repairable drivers.

Lesson 2 • Loudspeaker Construction and Failure Modes

Explains voice coil, cone, surround, and spider construction and how each fails. Component-level knowledge guides accurate diagnosis before disassembly.

Lesson 3 • Refoaming and Surround Replacement

Guides surround removal, centering, and adhesive application for foam surround replacement. Correct centering is critical to prevent voice coil rub after repair.

Lesson 4 • Headphone and Microphone Transducer Repair

Addresses headphone driver replacement, cable repair, and condenser microphone capsule issues. Transducer repair at this scale requires fine motor skills and precision tools.

Lesson 1 • Burn-In and Stress Testing

Explains extended operation testing to expose latent faults before equipment is returned. Burn-in catches thermal and intermittent failures that pass initial bench tests.

Lesson 2 • Repair Documentation Standards

Establishes formats for fault descriptions, parts used, test results, and technician sign-off. Thorough documentation supports warranty claims and future repair history.

Lesson 3 • Warranty and Liability Considerations

Covers repair warranty terms, liability limitations, and customer authorization practices. Clear agreements protect both the technician and the customer after service.

Lesson 4 • Performance Measurement and Verification

Covers frequency response, THD, noise floor, and channel balance measurements as final acceptance tests. Objective measurements confirm the repair meets the equipment's original specification.