Processing the audio signal
Michael Talbot-Smith · 2023
Equalization (EQ) means altering the frequency response of a signal. This chapter looks at EQ as a facility used in studio operations to modify the output of microphones, tape machines and other signal sources. While an operator will generally use his or her ears to decide how much EQ to use in any particular situation it is nevertheless useful to be able to carry out simple calculations. On the more complex and expensive equipment not only the centre frequency and &s;height&s; of the lift or cut is controllable but also the width. The latter control is often called &s;Q&s; from its similarity to the Q of a tuned circuit. A compressor is an automatic gain-control device. Typical uses include reducing the gain when there are high peaks in the audio signal which might otherwise cause overloads and hence distortion, and holding the level of a particular signal at a predetermined level.