I've got a student who frets that none of her pieces end up longer than 3 minutes. She's not wild about my advice: I tell her that one of the first decisions I make about any piece is the approximate length, like an artist deciding how large a canvas he's going to paint on (and, once finished, I usually find that I've hit it within 30 seconds). I tell her if she knows in advance that she's got to fill 11 minutes, then she'll compose differently.

Her music tends to be non-sectional, with a variety of ideas introduced in the first ten measures. I tell her that to write longer she'll probably need to either, 1. plan on having contrasting sections, or 2. husband her ideas and introduce them more slowly. It does seem to me that there's kind of an inherent, natural ratio between length and the rate at which new material is introduced. But I'm afraid that may only be relevant to the (screwy) way I compose. People who compose more organically than I do may have a different method. Does anyone have any other advice? Do most composers have a length in mind before composing? (I don't think writing vocal music with a long text, which can boost length, is an option for this student at the moment.) Deciding on a length in advance just seems too arbitrary to her. To me, that's "romanticizing" the composing process and putting too much faith in inspiration, but everybody's process is different. Thoughts?