Though the daring and energetic Blair Percussion VORTEX habitually defies summary, we can at least say that everything they do really looks like fun. Maybe that’s what has drawn such a range of talented collaborators to this polished but risk-taking student group over its three-year history. VORTEX’s spring concert renews the group’s partnerships with electric violin virtuoso Tracy Silverman and composers Mary Ellen Childs and Jeffery Briggs. Childs, whose inventively theatrical percussion ensemble Crash is a primary inspiration for VORTEX, has also written commissions for the Kronos String Quartet and the St. Paul Chamber Orchestra. She’ll be on hand as the group reincarnates her 1986 Still Life, intertwining her music with new computer-generated visuals. Silverman breaks out his solid-body electric violin for the premiere of his piece Scenic Overlap, and the program also features a newly expanded version of Briggs’ marimba quartet Ecliptic. Arrive early — this engaging ensemble typically fills the hall with listeners as well as with fresh approaches to music-making. Admission is free.