The latest instalment of The Sage Gateshead's eclectic Late Mix series featured two jewels of contemporary music. The Northern Sinfonia, under the baton of Clark Rundell, opened with Harrison Birtwistle's Secret Theatre; a complex and dramatic work that opens unexpected vistas in a unique soundworld. The piece, performed by a small ensemble with soloists constantly moving up to a platform to play melodic figures, demands incredibly virtuosic playing from each instrument and the building blocks seamlessly constructed. Percussionist Jan Bradley and pianist Lynda Cochrane drove the rhythm’s on with split-second timing. Having reached journey's end, the audience was transported to a hauntingly nostalgic landscape through Steve Reich's partly-autobiographical Different Trains. Reich's earliest memories were of being shuttled from coast-to-coast visiting his divorced parents. He found the trips exciting but later came to realise he would have had to "ride very different trains" had he lived in Europe during the same period as a Jew. He recorded his governess, a retired Pullman porter who worked the lines between New York and Los Angeles and three holocaust survivors, as well as the of steam trains and three string quartets. A string quartet under sinfonia leader Bradley Creswick played live over the pre-recorded tape, which was sensitively balanced by the sound engineer. The work requires incredible synchronism and the players kept pace with the constantly changing tempos in a gripping performance. A stimulating evening that fired up all those dormant synapses.