Alpha juno 2 emulator using CSound & Cabbage

This project is maintained by mikerodd



June-21 is an open source VST plugin emulation of the Roland Alpha Juno syntheziser series.

Sound Demos

Some simple demos to hear how it sounds…


June-21 can read and play Juno 1 / 2 MKS-50 presets. The emulator includes Juno 2 factory tones : “Preset” and “Memory”.

You can also find many presets here, you can test them with June-21 !

It’s still a work in progress, so not all presets will work as in the real gear, some presets might not be working.

The text and schematics are partly inspired by the original Juno-2 documentation.

The look of the GUI is obviously inspired by the Roland PG-300.

** Nota Bene:** June-21 is still in development and is not a perfect emulator, so some tones can be far from the real thing and some won’t work (but some can be very accurate and pleasing!). As of now (Dec 2019) some things are not implemented :


Linux - CSound must be present in the system Windows - a CSound runtime is in the distrib file