Audacity is free, open source, cross-platform software for recording and editing sounds.
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Audacity is a free, easy-to-use, multi-track audio editor and recorder for Windows, Mac OS X, GNU/Linux and other operating systems. The interface is translated into many languages. You can use Audacity to:
Record live audio. Record computer playback on any Windows Vista or later machine. Convert tapes and records into digital recordings or CDs. Edit WAV, AIFF, FLAC, MP2, MP3 or Ogg Vorbis sound files. Cut, copy, splice or mix sounds together. Change the speed or pitch of a recording. And more! See the complete list of features.