VOLTAGE CONTROL
With the oscillator, amplifier, and filter, a sound can be specified according to waveform, pitch, timbre and dynamic level. But without voltage control, a system consisting of these three building blocks has serious limitations. By using voltage control, the major parameters of the building blocks are made to respond to a dc or an ac voltage.
A voltage-controlled oscillator (VCO) has its pitch controlled not by turning a potentiometer, but by applying to it a control voltage .The cutoff frequency of a filter (VCF) or the gain of an amplifier (VCA) can be similarly controlled by a variable dc voltage.
For example, the amplifier shown in Fig. 25.3 has a conventional audio input but instead of using a potentiometer level control, ...
Get Consumer Electronics now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
