DEM-Osc — free synth for Mac (VST3 & AU)

DEM-Osc is a free synth from Clay and Kelsy Instruments. Five vintage oscillators — saw, triangle, square, sync, and chip — each raw-sampled from real analog and digital hardware. Stack three at a time through four hand-built convolution spaces, detune them, and let each voice drift into something warm and alive.

Five oscillators. Five wave shapes. Four convolution reverb spaces. 25 handcrafted presets that already sound finished. Key glide, vibrato, mod-wheel routing, and per-voice drift. The whole interface is hand-drawn — every knob. An instrument, not a settings page.

Free today, yours forever. It’s the doorway into our paid Osc Collection, but it’s a full instrument on its own — no crippled demo, no time limit. Mac only for now.

Download DEM-Osc free — or explore the full Osc Collection and our other free instruments.

DEM-Osc hand-drawn synthesizer interface showing five oscillators, envelope, and cutoff controls

Frequently asked

Is DEM-Osc really free?: Yes — completely free, with no time limit and no crippled features. It’s a full instrument and the free doorway into our paid Osc Collection.
What formats and OS does it support?: DEM-Osc is a standalone synth in VST3 and AU formats, for macOS.
What’s inside?: Five vintage oscillators sampled from real hardware, four convolution reverb spaces, and 25 handcrafted presets — with glide, vibrato, and mod-wheel routing.