Audacity
Audacity is an easy-to-use, multi-track audio editor and recorder for Windows, macOS, GNU/Linux and other operating systems.
Developed by a group of volunteers as open source.
Audacity provides you with a full set of tools that you can use to edit audio files and add effects through a clear and accessible interface. Users of all experience levels will benefit from this app’s intuitive interface and nice list of features.
PROS
Excellent resources: Despite the clarity of the interface, it can take some time to learn your way around this program. Fortunately, the app comes with links to a large collection of different types of resources to help you learn how to use all of its features. There is a Quick Help Guide, a full Manual, a Wiki, and user Forums where you can ask questions and get feedback from other users. All online resources for this app are searchable as well, so you can find what you’re looking for fast.
Lots of effects: The list of effects you can use on your audio files through this program is long and comprehensive. It includes items like Amplify, Auto Duck, Compressor, Hard Limiter, Leveler, and many more. You can also record your own voice directly through the app to add into an existing recording.
CONS
Additional downloads: You can import and export files in multiple formats through this app. But in order to access the full range of file format options, you have to download and install several additional programs.
BOTTOM LINE
Audacity is a versatile and comprehensive audio editing program. It runs smoothly, and the number of Help resources it comes with makes it a good choice for users of all experience levels. It is also completely free to download and use.