Heiner Goebbels' Walden, Midland Arts Centre, Birmingham, review Heiner Goebbels is the great hymner of urban experience. He loves its many-layered babble of voices and memories, and evokes them in entrancing and thought-provoking collages of sound, music, images and stage action. So Goebbels is really the last person you'd expect to be interested in Thoreau, the 19th-century American writer who built a house by an isolated pond in the woods, lived there in solitude for two years, and wrote a famous book about his experiences. We heard those lists during Goebbels" piece, along with other bits of down-home wisdom about the virtues of solitude ("For my part, I could gladly ignore the post office"). They were recited by the American Keir Neuringer, who was appropriately kitted out in a rugged check shirt. Between times he conjured unearthly glistening sounds from an assemblage of shining metal tubes called bowed chimes, and hammered vigorously at a wooden box. He even imitated the bird-calls. With him were four string players from Birmingham Contemporary Music Group, a double-bassist from Birmingham Conservatoire, plus six players from the Dutch Ensemble Klang. The music began with slow accretions of sounds from the assembled percussion, string quintet, synthesiser and wind, preceded by a deep electronic drone (the contrabass clarinet adding its deep, sinister growl). Later the drone gave way to more emphatically rhythmicised patterns on guitar or synth. At these moments one caught a whiff of 1970s jazz-funk bands like Weather Report, with saxophones soaring over a darkly intense chordal and drum backbeat. Though the music was notated the parts were not strictly co-ordinated, and the skill lay in the careful placing of each sound or riff in the most telling way. The Dutch players, who had made this slimmed-down version of the piece (with the composer's approval) performed with a certain swagger; the Birmingham contingent seemed somewhat tentative. The texts, the bird-calls, the emphasis on sounds of wood and metal sometimes struck sparks from the imagination. But the very urban palette felt strange for a commentary on a "life in the woods," and often the music seemed to be marking time, rather than filling it. It made me wonder whether Goebbels's normally sure instinct for the right subject matter had in this case led him astray. Part of the London 2012 festival