A woman sighs, moans, and cries out with delight - this isn't the
soundtrack from a late-night movie, but one of the works in a classical
music concert. It's a composition from 1919 by one of the masters of the
inter-war avant-garde in Czechoslovakia, Erwin Schulhoff, and it's called
the Erotic Sonata, a solo for what the composer described as a
"mother-trumpet" - in fact a single female voice, a work with a
fascinating score of scribbles, lines and dots.