Purity 1.3.9 for Mac was available as a free download on our application library. This Mac app is an intellectual property of Sonic Cat Inc. The software lies within Audio & Video Tools, more precisely Music Production.
From the developer:
PURITY is a next generation of digital musical instrument workstation and PCM sound module software. PURITY is designed to realize and surpass the hardware musical instrument workstation perfectly on computer-based music production environments offering higher sound quality and more usability.
You may want to check out more Mac applications, such as Band-in-a-Box, iRingtones or NanoStudio, which might be similar to Purity.