OverviewAudacity is a free, open-source application that lets you record audio on multiple tracks, modify the recorded audio, and mix / export the resulting audio as a single audio track in a variety of audio formats.
PublisherAudacity is published on the SourceForge site, and as with many open source projects, there are a number of different developers who contribute to its development.
Software Description - What You Get
After downloading and running the installer for your particular platform (Audacity works on Windows, Linux & Mac operating systems), starting up the application brings up the main Audacity window. There's the usual control toolbar features along the top, and then the main section of the application window relates to audio tracks (either recorded or imported) that are being used in the current project.
The following screenshot shows the application with a few different audio tracks being used in a project:
You can add as many audio tracks in a single Audacity project as you like. These can be created within a project by either importing audio from an existing track (e.g. an MP3 or WAV file), or by recording audio from an instrument connected to your PC's mic/line in sockets (e.g. a guitar or keyboard signal).
A 'label track' can also be added to the project, which is a way of annotating sections of the track, e.g. in the screenshot above, I've shown where the solo starts in the track, and the chorus section.
Once you have some audio tracks in an Audacity project, there are several tools and effects for editing & modifying the audio. Some of these are:
When a particular section of audio is selected, there are many different effects or filters that can be applied, such as 'click removal' (to remove noise elements, e.g. dust noise from an LP), and 'Equalization' (emphasizing or de-emphasizing certain frequencies).
It also has effects that let you change the pitch or tempo of the track, here are a couple of screenshots of those effect dialogs:
When recording and mixing audio, there is a 'meter toolbar' control that lets you control the left & right audio volume, or the recording level of the instrument being recorded.
There is a 'quick mix' feature, where you can combine several audio tracks into one. This can be useful for example where you have a guitar solo part, and you have re-recorded particular sections of the solo. This results in two different audio tracks, you can use the 'quick mix' feature to combine these two tracks into one guitar solo audio track.
Finally, you can adjust the left/right panning of any of the tracks, and export the audio to a single audio file, either WAV or MP3 files. In order to export MP3 files, you'll need to download a free MP3 encoding add-in file, more info about this can be found on the Audacity site.
SupportThere is plenty of support for Audacity on the SourceForge site, and there are also forums where you can post questions or issues. Being an open-source product, there are usually plenty of developers contributing, and so plenty of people to help!
Overall - Our Verdict
Audacity is a really great free tool for multi-track recording & editing. It has a simple but effective and easy to understand layout & interface, and compares well with other similar tools (e.g. Cakewalk). The benefit of being an open-source project is that there are plenty of additional features, effects and plug-ins available to use, and more are being created all the time.
I liked the way Audacity makes it easy to navigate around audio tracks, zooming in/out, and the wide range of different effects.
One minor negative point, I'm not sure if there's a way around this, but there didn't seem to be any way to carry on recording within the same audio track. For example you might have a guitar solo track, and record a section of the solo, then stop for a while before recording the next part. It seems that the best way to do this in Audacity is to record the different sections of the solo as multiple tracks, then mix/merge them together afterwards.
Overall, Audacity is a very useful (& free!) multi-track audio editing package.