Cumulus is a free software synthesizer developed by Loomer. Available format(s): VST, Audio Unit, RTAS for Windows, macOS.
Cumulus is a granular sampler which radically transforms sample content by breaking it into tiny slithers of audio called grains and reorganizing them to form new sounds. Cumulus is capable of a wide ranges of timbres: from evolving atmospheric soundscapes; to organic physical textures.
Up to eight Scenes can be created; a Scene corresponding to a particular sample position and set of synthesis parameters. Scenes can be played in realtime via MIDI, or arranged internally using the built-in sequencer.
Cumulus is available free on the cover-mounted DVD of Computer Music magazine.
http://www.loomer.co.uk/