Self on Audio, 3rd Edition

Chapter 3Precision preamplifier

(Wireless World, October 1983)

By the time the Precision Preamplifier of 1983 was conceived, the remarkable 5534/5532 opamps were available at a reasonable price, and delivered very low noise with then almost unmeasurable distortion, given a few simple precautions. It became clear that even if ultimate performance was the goal, it was no longer economical or sensible to assemble eight or more transistors into a homemade discrete opamp. The adoption of opamps meant a return to dual regulated power supplies, but time and progress had made this option less costly than it had been when the Advanced Preamplifier was designed. The supply rails were ±15V rather than the ±17V, which I later made universal for powering ...