Build a MOSFET Citation 12 — Nelson Pass / 1981

Audio Amateur has published a number of projects modifying popular kits, usually Dynaco's. Obviously it is much less expensive to use the chassis and power supply, pots, connectors, switches, PC boards, and heat sinks that can be had for the price of a kit than to buy the components individually or have them made. Creating a one-off copy commercially typically costs as much as making 10 copies of the same item, because the dominant costs are design and set-up time which do not increase with quantity. Small wonder then that most technicians and designers who write for this and similar… More...

Cascode Amplifier Design — Nelson Pass / 1978

Lowering distortion in power circuits without compromising their transient response remains a primary problem for designers of audio power amplifiers. Until fairly recently, the favorite technique for removing distortion components in linear amplifiers was to cascade many gain stages to form a circuit having enormous amounts of gain and then using negative feedback to control the system and correct for the many errors introduced by this large number of components. While the sum of these components' distortions may cause large complex nonlinearities, the correspondingly large amounts of feedback applied are generally more than equal to the task of cleaning up… More...