High Zero is an annual festival of Experimental Free Improvised Music hosted in Baltimore, Maryland, United States starting in 1999, and is one of the largest Free Music festivals in the US, if not the world. It is hosted by the Red Room Collective, a volunteer group that sponsors weekly concerts in improvised music and experimental theater, film, poetry, etc. in a side room of Normals Books and Records. Since 2001, the festival has been hosted at Baltimore's Theatre Project space.
The festival focuses on non-idiomatic improvisation, vocal improvisation, instrument building, electronics, sound art, and community events. The main theatre-based performances aim to bring together improvisers who typically have never played together previously into novel live situations in front of festival audiences, creating, potentially, a new experiences for both audience and performer.
High Zero draws from a large, international base of improvisors of many backgrounds, but traditionally gives half of the invitations for performance to Baltimore-based musicians and the other half to people from "elsewhere," whether that's Japan, thousands of miles away, or Philadelphia, about a hundred miles away.
High Jinx, a part of the festival focused on site-specific and community events, is a unique appendix to the festival. Typical events include a musical bike ride, an invented instrument band, a parade through Fells Point, and other outdoor performances, many of them punning and witty.
The festival has yielded six CDs on the Recorded label, each based around a particular performer (in order of release: Carol Genetti, Joe McPhee, Katt Hernandez, Jack Wright, Oleyumi Thomas and Neil Feather), which have, as a result of the festival's format, yielded documents of scarcely documented performers, including John Berndt, Paul Hoskins, John Dierker, Jason Willett, Catherine Pancake, James Coleman, Sean Meehan, Michael Johnsen, Jerry Lim, Ian Nagoski, Dan Breen, Dave Gross, Andy Hayleck, Helena Espvall, Evan Rapport, Keenan Lawler, Christopher Meeder, and Jim Baker.