Steve Reich (b. 1936) is one of the leading exponents of minimalism, a way of composing which uses repeated patterns of notes that gradually change over time. If that makes it sound mechanical and soulless, well the Reich piece in this week's Great Moments in Classical Music is anything but. Different Trains, written for string quartet and tape in 1988, brings together childhood memories of long rail journeys across America from coast to coast with the fate of Jews bundled into rail carriages in war-torn Europe; Sandy Burnett explores the techniques and the soundworld of this fascinating work.