Audio Power Amplifier Design by Douglas Self, a 13.7 MB PDF book. The title is a well-known engineering reference on solid-state amplifier topologies, distortion mechanisms, output stages, protection, thermal stability and power supplies. The edition is not stated in the name. Technicians repairing or modifying amplifiers use it to understand why a circuit is built as it is, how bias and stability are set, and which faults cause distortion or oscillation, making it a theory companion rather than a single-unit schematic.
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