The concert Wednesday, March 16, at Constellation was the first U.S. performance by Spunk, a quartet of Norwegian woman who have been improvising music under that name since 1995. Actually, as it turned out, it wasn’t quite a performance by the full group; cellist Lene Grenager wasn’t able to play due to an illness. But the rest of Spunk — Maja Solveig Kjelstrup Ratkje on voice and electronics; Kristin Andersen on trumpet, recorders and flutes; and Hild Sofie Tafjord on French horn and electronics — played as a trio, making some gloriously peculiar sounds. The absence of cello may have caused the mix to lean more heavily toward electronics, but it was really all about the way all of the noises blended together into shapes and textures. Bassoonist-composer Katherine Young opened the concert with similarly strange explorations of imaginative soundscapes.