The "Trihedron" series (the first you see when you enter Guest Spot at the Reinstitute), consisting of five, 1-foot- by-1-foot panels with lines of tape meeting to form an image that resembles one of the pyramids, is Hannum's peculiar process at its most hypnotic. In particular, 'Trihedron II,' in which the tape left on the panel reflects a gradient, looks more like a graphite drawing, hazy and barely there, like a mirage of a pyramid. This is one of the charms of Hannum's outré process: Who the hell knows what tape looks like in this context, let alone the ferric leftovers of musical data when it's stuck on a panel and tediously torn off? So, you find yourself reaching for comfortable precedents: graphite, large swaths of black paint, electrical tape. As for artists, well, Barnett Newman perhaps, or Ellsworth Kelly, only, you know, a lot more metal.