WavPack 5.1.0 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. This free software for Mac OS X is an intellectual property of Conifer Software. The software lies within Audio & Video Tools, more precisely Music Production.
From the developer:
WavPack is a completely open audio compression format providing lossless, high-quality lossy, and a unique hybrid compression mode. For version 5.0.0, several new file formats and lossless DSD audio compression were added, making WavPack a universal audio archiving solution.
In the default lossless mode WavPack acts just like a WinZip compressor for audio files.
You may want to check out more Mac applications, such as Golden Ear, Subsonic or Cog, which might be similar to WavPack.