Most jam-rock bands are horrible, because they don't know when to solo and when to cooperate. Worse, they don't know when to shut the fuck up. Exception: Hovercraft. This trio creates heavy acid-freakout music that verges on experimental wankery without playing the same repetitive riff too long or straying into the forbidden self-indulgence zone. Experiment Below is a seven-song, 45-minute marriage of effects and guitar sounds sure to affect you in one way or another. In subdued moments like "Wire Trace," Hovercraft sounds like an experimental ambient project, only with a grating quality more likely to create tension than relaxation. When the volume and intensity are tweaked, it becomes more difficult to classify. Whether playing space-rock, industrial, psychedelia, Hovercraft's loudness and intensity rivals the best of them. ("Them" being unqualifiable peers such as Zen Guerrilla or Helios Creed.) The main difference between Hovercraft and those peers is Hovercraft's accessibility. The material isn't so dense as to be impenetrable or overwhelming, and it's produced clearly enough that the instruments don't get buried in the mix, making Experiment Below a good platform from which to dive into current experimental music.