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, and it's yours to keep, with no trial and no timer. A few of the deeper effects are saved for the collection. The plugin is for Mac, and there's a Kontakt version for Mac and Windows.

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. It's yours to keep, with no trial and no timer. A few of the deeper effects are saved for the paid Osc Collection, and DEM-Osc is the free way in.
What formats and OS does it support?
There are two versions, and both are free. The plugin is VST3 and AU for macOS. The Kontakt version runs in the free Kontakt Player on Mac and Windows, and you add it in Native Access with the serial we email you.
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.