One of Xenakis's achievements was in evoking a recognisable (though never traditional) sonic context, against which sound could express itself in directly musical terms. Thus we get the Homeric landscape of Aroura (1971) with its heightened interaction between violent gestures and an even more intense silence, and the transcendental virtuosity of Theraps (1976) - its succession of powerful images redefining the double-bass persona. Much to respond to, then, in these assured performances by Ensemble Resonanz (John Eckhardt a bassist of stature), recorded with an ideal combination of clarity and spaciousness.