Designing Audio Circuits

How does speech, music, or, indeed, any sound get from the record, the CD or the cassette tape to the loudspeaker? This is a question that many people keep on asking and to which this book endeavours to give a comprehensible answer. Understanding the background of the process is a first requirement, which is why the author in the description of single components makes clear what exactly happens in the component. An understanding is also engendered of phenomena such as noise, hum, distortion, and others, as well as standards such as the decibel and the RIAA characteristic. Designing circuits is practically impossible without an understanding of the various networks involved in the conversion of the input sound to the sound emanating from a loudspeaker. To this end, the author describes four important basic circuits using an operational amplifier, a component without which modern audio circuits can no longer be imagined. Variants of these four circuits return in many of the other circuits contained in this book. Building circuits, including ancillary and special ones, form the practical parts of this book. These circuits can be applied in audio equipment as well as with certain musical instruments. There are preamplifiers, filters, output stages, power supplies, compandors, mixer panels, level meters, bandwidth limiters, headphone amplifiers, playback stages, as well as tips on construction and faultfinding.