Fifth CD already for the collaboration between Alva Noto and Ryuichi Sakamoto. We know the drill: modest background glitches and drones used as foundation for delicate, introvert piano, the whole thing embracing minimal aesthetics full-force. And still, there's no denying that both musicians are the best of their distinctive breeds, or that "Summvs", as its four predecessor, is a successful exercise in elegant beauty. Add two covers of Cluster and the use of some experimental piano to the mix, and you get something which, yes, of course, is mandatory.