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Yup, it is possible to mix multiple tracks in Audacity. It's also possible in Sound Forge, Wavelab, or any other editor. But it's not a multitrack. It's an editor. It's multitrack support is an ...

Audacity, an open source multitrack audio editor, has versions for Linux/Unix, MacOS and Windows. If all you do with audio files is play them, then Audacity could be much more than you need. This is ...