"The microtonal playing on the trombone is notated so that there are six steps between each semitone. Any changes of dynamics (pp and thereabouts for both instruments) should be, like changes in breath, as imperceptible as possible. The piano should sound absent minded, without regularity or presence. If there is at some point a very short sound on the trombone it can be extremely loud, inexplicable" (Cage, "Performance Notes").This product is Printed on Demand and may take several weeks to fulfill. Please order from your favorite retailer.John Cage