Monday, October 7 2:00 pm – 4:00 pm
SESSION K: RECORDING AND REPRODUCTION OF AUDIO

Chair: Bob Moses, Island Digital Media Group, Vashon, WA, USA

K-1 Power Supply Regulation in Audio Power Amplifiers—Eric Mendenhall, Gibson Labs, Redondo Beach, CA, USA

Audio power amplifiers have typically been supplied power by the simplest possible means, usually an off-line supply with no line or load regulation, most commonly based on a line frequency transformer. Even modern amplifiers utilizing switch-mode power supplies are usually designed without line or load regulation. The exception has been made for high-end audiophile amplifiers. The pros and cons of a regulated power supply are investigated.
Convention Paper 5694

K-2 Audio Power Amplifier Output Stage Protection—Eric Mendenhall, Gibson Labs, Redondo Beach, CA, USA

This paper reviews a progression of circuits used for protecting bipolar power transistors in the output stages of audio power amplifiers. Design oriented methods of determining the protection locus are shown in a mathematical and graphical procedure. The circuits are then expanded from their standard configurations to allow for transient excursion beyond steady state limits, and thermally dependent protection limits, to better match the protection limits to the actual output stage capability. This allows the protection scheme to prevent output stage failure in the least restrictive way. A new method is shown for achieving a junction temperature estimation system without the use of a multiplier.
Convention Paper 5695

K-3 Archiving Audio—Jim Wheeler, Tape Restoration & Forensics Company, Oceano, CA, USA

Hundreds of millions of tapes are deteriorating. As these tapes age, more and more of them will begin deteriorating. This paper describes how to recover these unplayable tapes as well as how to store them properly. This paper will also cover all of the issues of archiving audio, including high-capacity and inexpensive hard disk drives, as well as equipment obsolescence and new media.
Convention Paper 5696

K-4 Finding a Recording Audio Education Program that Suits Your Career Choice—Laurel Cash-Jones, Burbank, CA, USA

This paper discusses the past, present, and future of recording audio education. It describes how the job market and educational requirements have changed, and takes a look at how to plan for a successful career. It also provides valuable information on getting and keeping a job in today’s fast-paced world of professional audio.
Convention Paper 5697