Suppression circuit for loudspeaker switching transients - uses photo resistor to eliminate switching transients being transmitted as audio effects

摘要

A photo resistance element is built into a loudspeaker circuit of the type used in audio meters, to suppress clicks caused when range switching occurs. The output of a sine wave generator (10) is amplified (11) and is processed by a voltage divider (12) to control the signal volume level. The divider output is compared (15) with the output of a photo resistor (13) that is switched by a lamp (16). When range switching occurs, the presence of the photo resistor introduces sufficient delay to eliminate any transients.