Greenoak Crystal v2.5.5 (MacOS/Win) [FREE]

Greenoak Crystal is a free semi-modular synth plugin for producers who want to build sounds with subtractive synthesis, FM, and detailed modulation. It also includes wave sequencing and granular synthesis, giving hobby musicians and sound designers several ways to explore textures beyond a basic synth patch.

More than 90 parameters can be modulated, while graphical multi-stage envelopes let you shape how a sound changes over time. Envelopes, LFO rates, and delay times can follow your project tempo, making Crystal useful for rhythmic patches as well as slowly evolving tones. Program morphing adds another way to move between sounds, and MIDI learn helps connect controls to your hardware.

Built-in chorus, flanging, comb filtering, and echo effects provide further sound-shaping options. A band splitter lets you process different frequency ranges separately, while SoundFont import expands the material available for patch creation. Crystal runs inside a compatible plugin host rather than as a standalone application. Windows users should check their DAW’s VST2 support before installing; the listed formats also include AU for compatible Mac hosts.