Macros
Batch processing in Audacity is effected by processing a Chain of effects in preset order, either on tracks in the active Audacity project window or on a number of imported audio files. This can save time and repetitive effort. Chains are often used to batch process a group of audio files with the same sequence of effects or functions. Examples of typical usage:
- Compressing the dynamic range of a number of WAV files, then converting them to MP3
- Noise removing, bass boosting then normalizing a track or tracks in a project
How to use Chains
In order to use batch processing it is necessary first to set up a Chain of effects using the Edit Chains command. A "Chain" is a sequence of automated commands similar to a "macro". Once the Chain has been set up you can then use the Apply Chain command to implement it.
Edit Chains
Enables you to either edit, remove or rename existing Chains, or add a new Chain. The Chain can include a number of common Audacity functions and effects to be executed in any order you specify. In many cases, the parameters for each command in the Chain can be specified within the Edit Chains window. Any built-in or Nyquist effect shown in the Effect Menu can be added to a chain, along with an Export command to save an audio file.
Apply Chain
Enables you to select a Chain and apply it to either the entirety of the current project, to single audio file or to a group of specially selected audio files.

