ProPhase 2.3 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. The most popular version among the program users is 2.0.
The software lies within Audio & Video Tools, more precisely Music Production. This Mac application was originally developed by Katsura Shareware. We recommend checking the downloaded files with any free antivirus. The unique identifier for this application's bundle is com.katsurashareware.ProPhase.
From the developer:
ProPhase is a professional digital audio software tool that displays detailed information on the phase, levels and mono compatibility of stereo audio signals in real time.
You may want to check out more software for Mac, such as M-Audio Key Rig or Speak, which might be related to ProPhase.