PaulXStretch
“PaulXStretch is designed for radical transformation of sounds. It is NOT suitable for subtle time or pitch correction. Ambient music and sound design are probably the most suitable use cases. It can turn any audio into hours or days of ambient soundscape, in an amazingly smooth and beautiful way.
Extreme Time-Stretching
This application/plugin is based on the PaulStretch algorithm (Paul’s Extreme Time Stretch, originally developed by Nasca Octavian Paul), and specifically the PaulXStretch version from Xenakios. The UI has been updated, adapted for various screen sizes, and built for the latest platforms.”