Audacity 2.0 - Audio recording, editing and mixing tool.. (Free): "
Audacity is a free audio recorder/editor/mixer. You 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 together, 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.
- Fixed playback speed and synchronization problems when dragging clips or tracks between tracks having different sample rates.
- (Windows) Removed a crash risk where shortcuts could be used to record or import in one project while importing or exporting in another.
- Fixed crashes when changing the sample format of read-directly WAV or AIFF files using the Track Drop-Down Menu.
- Fixed a crash importing MP3 files that had duplicate metadata tags (this is a bug in current libsndfile which has been patched in Audacity; MP3 files mislabeled as WAV which have duplicate tags will still crash Audacity on Linux if Audacity has been compiled against an affected version of system libsndfile).
- Fixed an issue where excessively high or corrupted sample values in the audio could corrupt exports from the start of the problem for the rest of the file, and could corrupt the rest of the project.
- (Linux) Fixed Audacity could not be compiled against FFmpeg 0.7.x and 0.8.x.
- Fixed crash on launch when using "Ambisonic Decoders (PC)" VST plug-ins and other plug-ins that enable additional floating point exceptions.
- Fixed Plot Spectrum background could be transparent on some machines.
- Bug fixes for Click Track, High Pass, Low Pass and Vocal Remover.
- Chirp, Tone and Silence generators now remember their settings.
- New Interface preference to show the track name in the display (this is off by default).
- Longer default Playback preference for effects preview and preview before cut.
- Restored use of Page Up and Page Down to scroll horizontally.
Mac OS X 10.4 or later
(Via MacUpdate - Mac OS X.)