Compressors and Limiters

Compressors and limiters have a lot of different applications in the audio world.  Most commonly, they are used to even out dynamics in any performance.  Compressors make the loud and quiet passages closer in volume to each other, providing a more consistent performance.  They have all sorts of applications in pro audio, whether helping out a weak performance, preventing clipping, mastering a final mix down of recorded audio to make the overall mix louder, preventing quiet parts from being drowned out in the mix, or to make up for bad mic technique with the vocalist.

Compressor– Used to reduce the dynamic range of any signal.  Compressors turn the loudest parts of the audio down.   Once the loud parts are compressed and there is a significant change in volume, the output level can be used to return them to their original volumes, thus, making quiet passages louder.

Limiter- is a compressor with some higher settings on the ratio.  Using a high ratio makes it very hard for incoming audio to make any real volume changes on the compressor’s output.   This creates “limit” for how loud the audio can go.  Therefore, compressors with high ratios are called limiters.  In order to set a “limit”, you will want to set a fast attack time to prevent transients from sneaking through unaffected.  Limiters are commonly used in the mastering and mixing world for making an overall mix louder.