[on his compositions for groups of musicians playing the same instrument] I'm asking the performers and the listeners to live in a particular sound world. For some people it's very easy, for some people it takes time, and some people can't do it. I think of it as entering a climate or environment. You know, you walk into the desert and go, 'Oh, it's hot and it's bright, and all I can see is sand'. Some people are going to go, 'I don't want to be here', but someone else will go, 'Wow, it's really hot and bright and all I cans see is sand, but I'm starting to get used to the climate and I'm noticing things, and this is actually a fascinating climate'.