The fourth issue of 1974 marks a major milestone for The Audio Amateur, celebrating five years of precision DIY engineering. Here are the highlights of this anniversary edition:
- Editorial: Five Years and the Power Struggle: Reflect on the magazine's first five years and dive into the high-stakes battle between Dynaco and the FTC over controversial new amplifier power rating regulations .
- Moore’s Precision Preamp: Build a high-performance, low-level building block for your magnetic phonograph cartridges or tape play heads. This versatile circuit is optimized for low noise, high gain, and extreme accuracy in frequency compensation .
- SME Shell Surgery: Don't let excess mass muddy your sound. Learn how to perform precision "surgery" on your SME 3009 headshell to reduce dynamic mass, significantly improving the tracking of modern high-compliance cartridges .
- IC Regulated Power: Master the art of "electronic" hum removal. Walt Jung continues his definitive series on op amps, providing schematics for high-performance voltage regulators that deliver the ultra-stable, ripple-free power required for top-tier audio .
- An IC Preamp Operation Manual: Now that you’ve built the TAA IC console, learn how to "fly" it. This detailed guide covers everything from managing cue sends and master faders to professional techniques for aligning your tape recorders .
- Audio Aids & Comfort: Discover ingenious reader-submitted solutions, including a proposal for a high-frequency tube power supply and a clever "kitchen-table surgery" technique for repairing broken AC adapter wires .
- Kit Report: SWTP Headphone Amplifier: Get the expert verdict on Southwest Technical Products' Class A headphone amp. This report evaluates its "clean, open" sound and offers critical advice on managing its considerable heat dissipation .
- Tapeniques: A Slide Show Saga: Elevate your multimedia presentations. Learn the professional secrets of synchronizing audio narration and music with slides, including expert tips on scriptwriting and final editing .
- Classic Circuitry: The Marantz 7C: Study the engineering of a true audio icon. This issue includes the complete, detailed schematic for the Marantz 7C Stereo Preamplifier, an essential reference for restorers and tube enthusiasts .
Table of Contents
- Editorial: Take Five and Overzealous Overshoot ................................................................ 2
- A Preamp for Magnetic Phonograph Cartridges and Tape Play Heads: by Richard R. Moore ................................................................................................................... 4
- SME Shell Surgery: by Fred M. Gloeckler, Jr. ................................................................... 12
- IC Regulated Power, Part III: by Walt Jung ...................................................................... 14
- An IC Preamp, Part 3: Operation Manual: by Richard A. Kunc ........................................ 22
- Audio Aids & Comfort: by readers Buvel and Levitt ........................................................ 26
- Kit Report: SWTP Headphone Amplifier: by Damon Hill ................................................. 30
- Tapeniques: A Slide Show Saga: by James K. Jobson .................................................... 33
- Classic Circuitry: The Marantz 7C Stereo Preamplifier ..................................................... 36
- Letters ..................................................................................................................................... 38
- Classified ................................................................................................................................. 45