Difference between revisions of "Compressor"

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{{ednote|'''Peter 2May14:''' [[ToDo-2]] This page is a potential candidate for deprecation, the material is, or should be, handled more than adequately in the Manual. }}
{{deprecated}}{{advice|This page has been transferred to the Audacity Manual - see [https://manual.audacityteam.org/o/man/compressor.html Compressor] in the Audacity Manual.}}
{{Introrel|Audacity's '''Compressor''' effect reduces "dynamic range" by making the loud sections quieter, then optionally amplifies the compressed audio to be as loud as possible without clipping. This increases the perceived overall loudness of the audio.||[[EffectsTips|Effects Tips]]}}
The terms of the Compressor effect are as follows:
* Threshold - the volume level at which compression starts to be applied. The further right the slider, the louder the input has to be before compression is applied.
* Ratio - if the level is above the threshold, how much it will be reduced. For example, a 3:1 ratio implies that a passage in the original audio that became 3 dB louder would only become 1 dB louder in the compressed result. The further the slider is to right, the stronger is the compression applied.
* Attack time - the amount of time the compressor waits to respond after the Threshold is reached
* Decay Time: - how soon the compressor starts to increase the volume level back to normal after the level drops below the Threshold
* Normalize to 0 dB after compressing - if this is checked, then after compression the audio will be amplified to the maximum amount possible without adding distortion
==Further reading==
There are some good (but not too technical) explanations of compression here:
* [http://www.harmonycentral.com/t5/Effects-Signal-Processors/Compressors-Demystified/ba-p/35515615 Compressors demystified]  (Harmony Central)
* [http://www.soundonsound.com/sos/sep09/articles/compressionmadeeasy.htm Compression Made Easy] with [http://www.soundonsound.com/sos/sep09/articles/compressioneasyaudio.htm audio files] (Sound On Sound)
More advanced:
* [http://www.soundonsound.com/sos/dec00/articles/adcompression.htm Advanced Compression Techniques Part 1] and  [http://www.soundonsound.com/sos/jan01/articles/advanced.asp Part 2]  (Sound On Sound)
<div id="alternative"></div>
== An alternative Free Compressor==
* '''Chris's dynamic compressor''' by the late Chris Capel is a popular [http://en.wikipedia.org/wiki/Nyquist_%28programming_language%29 Nyquist] plug-in that tries to even out abrupt changes of volume by employing "''lookahead''" (this attempts to anticipate volume changes by starting to apply compression before the volume rises to the threshold level). There are options to soften the softer audio and invert loudness. See instructions for [[Nyquist Plug-ins#Installation|Nyquist plug-in installation]]. Several versions of this plug-in may be downloaded.
** An archived 1.1 version of this plug-in can be downloaded by left-clicking [http://web.archive.org/web/20080705130736/http://pdf23ds.net/projects/compressor/compress.ny this link], then use the browser feature to save the web page in text format. Right-click and "Save Link As" or "Save Target As" may also work in some browsers. Archived documentation can be found [http://web.archive.org/web/20081120011622/http://pdf23ds.net/software/dynamic-compressor/ here].
** A more advanced 1.2.6 version of this plug-in can be downloaded [http://theaudacitytopodcast.com/chriss-dynamic-compressor-plugin-for-audacity/ here].
** '''Neither of the above versions can be modified or redistributed.''' We hope to make a freely-licensed version of this plug-in available for separate download later, based on Chris's 1.2.7 Beta version which has a free [http://en.wikipedia.org/wiki/MIT_License MIT License]. For more information, please visit http://forum.audacityteam.org/viewtopic.php?f=42&t=58958 .

Latest revision as of 11:42, 19 August 2021

Warning icon This page has been deprecated.
The information on this page are likely out-of-date and will not be updated in the forseeable future. It may be removed at any time.
Warning icon This page has been transferred to the Audacity Manual - see Compressor in the Audacity Manual.