Volumetric is a utility that converts the volume from your microphone (or another audio input) into MIDI and OSC signals. This behaviour is built into most VJ apps, but it may be handy if you have some software without this functionality.
It comes in two flavors. An online version and a standalone app.
If you only need MIDI and don’t care about OSC, simply point your browser (Chrome only at the moment) here: Volumetric online.
It will immediately start outputting a MIDI signal that corresponds to the volume level.
If you want the full functionality including OSC you can download the free app for Mac and Windows – download Volumetric.
Volumetric is open source and on Github