Audacity is a free audio editor that can record sounds, play sounds, import and export WAV, AIFF, and MP3 files, and more. Use it to edit your sounds using Cut, Copy, and Paste (with unlimited Undo), mix tracks, or apply effects to your recordings. It also has a built-in amplitude envelope editor, a customizable spectrogram mode, and a frequency analysis window for audio analysis applications. Built-in effects include Bass Boost, Wahwah, and Noise Removal, and it also supports VST plug-in effects. This is one of my favourite audio tools!
* Usability improvements
* New selection bar
* New features for label tracks
* Improved toolbar docking flexibility
* Menu renaming and reorganization
* Selection, ruler, and playback control improvements
* Major improvements to some built-in effects
* New Repair effect
* Improved Equalization effect
* Many fixes and minor improvements to other effects
* Improved accessibility for the visually impaired
* Improvements for screen readers, accessibility of tracks, and hot keys
* Timer recording
* Auto-save and automatic crash recovery
* New features and bug fixes for Nyquist