The Los Angeles ensemble Wild Up, often calling itself a collective, creates, in its own words, "projects that live somewhere between new music and theater and performance art and pop." Wild Up has collaborated with various traditional orchestras, rock bands, and cultural institutions.

Wild Up was formed in 2010 by Christopher Rountree, who remains its artistic director. His aim was to gather a group of young musicians who would create new classical music events that would live in the context of popular culture, performance art, and the musical avant-garde. Wild Up has 24 members from which varying combinations of individual musicians may be drawn for the project at hand. The group has held residences with such traditional institutions as the Los Angeles Philharmonic, the Los Angeles Chamber Orchestra, and the Hammer Museum. It became more widely known with a series of high-profile Los Angeles appearances in the 2013-2014 season, including making debuts at the Los Angeles Philharmonic's Brooklyn Festival, at the Walt Disney Concert Hall during the Minimalist Jukebox Festival, and performing at the Colburn School, the latter marking the beginning of an ongoing collaboration.

Beyond these events, Wild Up has engaged in collaborations with a wide range of musicians and other creative artists from many genres. The group has premiered hundreds of new works, including by Julia Holter and Juliana Barwick, and has worked with avant-garde pop figures such as Björk (whom Wild Up backed at the FYF Fest) and Scott Walker. Wild Up has championed the music of Black avant-garde composer Julius Eastman, who died in 1990. The ensemble has performed live film scores, including those for Under the Skin by Mica Levi and Punch Drunk Love by Jon Brion at the Regent Theater and Ace Hotel in Los Angeles. Wild Up performed a noise concert at the groundbreaking of a new Frank Gehry building in downtown Los Angeles and founded a winter solstice concert series called Darkness Sounding. Wild Up appeared on a 2019 recording of Christopher Cerrone's The Pieces That Fall to Earth on the New Amsterdam label (which was nominated for a Grammy Award for Best Chamber Music/Small Group Performance), and in 2021, the group released Femenine, the first in a series of recordings devoted to Eastman. ~ James Manheim, Rovi