In the 1930s-40s, a new kind of music was taking shape in the U.S., spearheaded by experimentalists John Cage, Henry Cowell, Lou Harrison, and others. New modes of expression unfolded as they explored music of the Far East and Africa, incorporating these exotic sound worlds into their own works. Challenging convention, they made music on non-traditional instruments and built percussion orchestras out of the detritus of the modern age – car parts, flower pots, slabs of wood, and plumbing pipes.