The 1974 issue 1 of The Audio Amateur kicks off the magazine's fifth year with a heavy-hitting lineup of classic modifications and advanced electronic theory. Here are the highlights to entice your inner audio engineer:
- A Perfectionist's PAS Preamp: Transform the classic Dyna PAS tube-type preamplifier into a state-of-the-art contender . David Vorhis details definitive modifications, including a regulated power supply and circuit simplifications, that strip away "graininess" to reveal a natural balance and startling detail .
- A High Efficiency Mid- and High Range Horn: Stop settling for mediocre, fuzzy transients in your speaker system . This project shows you how to build a fully horn-loaded enclosure for an inexpensive driver, achieving superior frequency response and the kind of "punch" that makes music sound like the real thing .
- Back to the Wall: Reclaim your floor space without sacrificing high-end transparency . Alan Watling demonstrates how to mount high-performance KEF and ribbon drivers directly into your walls, utilizing a "rigid" infinite baffle effect for a massive sound stage and deep, subtle bass .
- IC Op Amps for Audio: Master the technical foundations of modern audio design . Legend Walt Jung goes "Back to the Basics" with a deep dive into IC specifications, teaching you how to interpret manufacturer data sheets to select the perfect components for your custom projects .
- Learning to Use Transistors: Understand the critical bridge between voltage and power . This installment explores the mathematics of power gain and impedance matching, providing the essential knowledge needed to design efficient, high-performance multi-stage transistor amplifiers .
- Audio Aids & Comfort: This issue is packed with DIY ingenuity, from a clever "Stylus Saver" for AR turntables to advanced cooling techniques for "Tiger" amplifiers and high-performance "souped-up" op amp output circuits .
Table of Contents
- A Perfectionist's PAS Preamp: by David Vorhis ................................................................ 4
- A High Efficiency Mid- and High Range Horn: by James Nicholson ............................. 11
- Back to the Wall: by Alan Watling ..................................................................................... 16
- Audio Aids & Comfort: by readers Harris, Ferrand, and Anderton ............................... 20
- IC Op Amps for Audio: by Walt Jung ............................................................................... 23
- Learning to Use Transistors: by C.N.G. Matthews ........................................................ 28
- Letters ..................................................................................................................................... 32
- Classified ................................................................................................................................. 38
- Just Looking .......................................................................................................................... 36
- Advertiser Index ................................................................................................................... 15