If you are running an older Mac system (pre-Catalina), you might find legacy versions like MetaSynth 2.5 hosted on sites like the Internet Archive
The Rise and Fall of Metasynth: Understanding the Cracked Version and Its Implications
MetaSynth is a specialized "image-synth" software used for sound design that converts visual data into audio, famously utilized for experimental music and film sound design. Due to the high cost and specialized nature of the software, users are advised to avoid cracked versions and instead utilize legitimate alternatives such as Virtual ANS, Photosounder, or Coagula to explore image-to-sound synthesis safely.