Upward compression still reduces dynamic range, but does so by raising the volume of quieter elements, as opposed to attenuating louder ones.Įxpansion, meanwhile, is a similar process but one that serves the opposite purpose to compression - increasing the dynamic range of an audio signal rather than squashing it.įortunately, the freeware realm has all of these compressor types covered, and if you’re confused about how and when to apply each the best thing to do is simply download a variety and experiment.

You’ll also come across terms like upward compression and expansion, both of which flip standard compression on its head. A limiter is essentially just a compressor set at a high ratio - ie, the amount of compression applied above the threshold - so that it completely cuts off all peaks over a certain level. We’ve included some plugins labelled as limiters below, too.

The former tackles the whole frequency range at once, while the latter can be applied to low, high or mid range frequencies independently. Then there are broadband or multiband compressors. Transparent compressors aim to do their job without you noticing they’re there, controlling dynamics but remaining as faithful as possible to the input audio.Ĭharacterful compressors, which are often emulations of vintage hardware, may alter the sound of your audio slightly, usually through subtle EQ or filtering, or by adding a touch of musically-pleasing distortion. One of the main divides in compressor types are those described as transparent and those that are ‘characterful’.

Audacity limiter plugin