The best solo wind-instrument improv is rather like a Houdini show: there are moments when you're genuinely worried if the performer will be quite all right. Listening to Fibres - an hour of fascinating, grisly soprano-sax improvisations � you have to wonder whether by the session's end Rives was stretched out on the floor hyperventilating. Its seven tracks explore three different technical/musical areas at length; each involves a single, overwhelming sound Rives unpacks systematically, as well as fleeting ghost tones and other half-audible layers of activity. The centrepiece of "Larsen et le roseau" (presented in two versions) is an atrocious high-pitched wail which on part 1 he pushes to migraine intensity; part 2, though double the length, is on the whole less harrowing. The three "Granulations" form a three-movement symphony of spit. Part 1 is thirteen minutes of controlled gargling, part 2 offers six minutes of what sounds more like sucking than blowing (so intimately recorded as to suggest a dentist's vacuum), while part 3 gets a deeper, ickier kind of clogged-drain bubbliness. In the context of this disc "�branlement 1" is a bit of a reprieve (a throbbing drone that's by no means unpleasant to listen to), but listeners had better not lower their guard, as "�branlement 2" turns out to be the harshest thing on the disc - four minutes of godawful jet-take-off screech. I recommend Fibres highly: not only is it a remarkable album - anyone who's a keen follower of solo improv ought to check it out pronto - but it's also handy to have around in case you need to clear a room.