Designing Audio Circuits and Systems

Bob Cordell is an electrical engineer who has been deeply involved in audio since his adventures with vacuum tube designs in his teen years. He is an equal‑opportunity designer to this day, having built amplifiers and preamplifiers with vacuum tubes, bipolar transistors, JFETs and MOSFETs, and is a prolific designer of audio test equipment, including a high-performance THD analyzer and many purpose-built pieces of audio test gear. He has published numerous articles and papers on power amplifier design and distortion measurement in the popular press and in the Journal of the Audio Engineering Society. In 1983 he published a power amplifier design combining vertical power MOSFETs with error correction, achieving unprecedented distortion levels of less than 0.001% at 20 kHz. He previously published the book Designing Audio Power Amplifiers. Bob is an avid DIY loudspeaker builder and has combined this endeavor with his electronic interests in the design of powered audiophile loudspeaker systems. He also consults in the audio and semiconductor industries and has presented audiophile listening and measurement workshops with his colleagues at the Rocky Mountain Audio Fest and the Home Entertainment Show. As an electrical engineer, Bob has worked at Bell Laboratories and other related telecommunications companies, where his work has included design of integrated circuits and fiber optic communications systems. Bob holds 17 patents and has presented numerous papers at the International Solid State Circuits Conference (ISSCC), the Convention of the Audio Engineering Society and other related professional meetings. Bob maintains an audiophile website at www.cordellaudio.com where diverse material on audio electronics, loudspeakers and instrumentation can be found.

1. Introduction 2. A Simple Preamplifier Design 3. Circuit Building Blocks 4. Passive Components 5. Surface-Mount Technology 6. Poles, Zeros, Networks and Bode Plots 7. Semiconductors 8. Operational Amplifiers 9. Negative Feedback 10. Noise 11. Filters 12. Distortion and Its Measurement 13. Switches and Relays 14. Power Supplies and Grounding 15. Moving Magnet Phono Preamplifiers 16. Moving Coil Phono Preamps 17. Tape Preamps and NAB/IEC Equalization 18. Microphone Preamps 19. Balanced Inputs and Outputs 20. Equalizers and Tone Controls 21. Headphone Amplifiers 22. Volume, Balance, Fader and Panning Controls 23. Digital-to-Analog Converters 24. Active Crossovers and Loudspeaker Equalization 25. Voltage-Controlled Amplifiers 26. Compressors and Other Dynamic Processors 27. Level Displays and Metering 28. Microcontrollers and Microcomputers 29. Mixers and Recording Consoles 30. DI Boxes and Microphone Splitters