Compressors allow for better control of volume, by automatically increasing or decreasing an audio source’s level depending on its volume. Compressors are generally used to decrease the level of an input that often spikes in volume.
There are generally five parameters of compression that can be adjusted:
- Ratio: The rate at which a compressor engages.
- Threshold: The level of volume where the compressor engages.
- Attack: The time that it takes for a compressor to engage after the input volume surpasses the threshold.
- Release: The time that it takes for a compressor to disengage after the input volume goes below the threshold.
- Gain: the amount of gain that can be added after compression processing to make-up for the volume lost in compression (sometimes called Makeup Gain).