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Dynamic Range Processors

Dynamic range processors include compressors, limiters, expanders and gates and are used to control the loudness of recorded sounds. Compressor and limiters keep loud sounds from overwhelming the mixed recording or sound system. Expanders and gates eliminate background noise from recordings. All four share a common control: the threshold control. Compressors and Limiters attenuate amplitudes higher than the threshold, thus keeping the overall volume lower. Expanders and Gates attenuate sounds softer than the threshold, so background noise is less noticeable.

Each signal processor type has a specific purpose in sound recording. Compressors are the best choice to raise the level of soft recordings or increase the aparatent volume of vocals, soloists or other important tracks. Limiters protect sound systems from overload or damage; they should not be adjusted so their limiting action occurs all the time.

Expanders are a good choice if one wants to subtly reduce background noise since the ratio control determines the amount of signal reduction. Most engineers use gates when sound from other tracks can cover up the abrupt silences caused when the gate closes..

The demonstration files show how the attack, release, ratio and threshold controls impact the sound processed by compressors, limiters, expanders and gates. The drills have you match the settings of the processors with pre-recorded material.