Journal Article
Audio Automatic Volume Control Systems
Journal of the Audio Engineering Society · Volume 1 · Issue 4 · pp. 310–316 · October 1953
Abstract
Applications for audio automatic volume control circuits are listed and categories defined. Circuits are broken down into their elements and discussed separately. Control elements described include pentodes, saturable reactors, nonlinear diodes, positive and negative temperature coefficient resistors, and mark-space devices. The thump present in single-ended systems is pointed out, and several means for its elimination are described. These include push-pull circuits, bridge circuits, cascaded stages with networks between and cross-connected suppressor-controlled pentodes. Means for obtaining control voltage are outlined, and the advantages of double circuits enumerated. Filter circuits are treated in a discussion of the problems incurred in securing fast operate time. Both forward- and backward-acting circuits are shown and compared from performance and cost standpoints. Measurement techniques are briefly described.
