Onetime Loop guitarist Robert Hampson’s several-year-old Main project moves beyond a blatant deconstruction of his last band’s more conventional feedback-drenched psychedelic rock. Drawing from the electronic ramblings of Tangerine Dream, the guitar-driven lunar fairy tales of ’70s prog-rockers (Can), and the airy soundscapes of today’s ambient masters (Paul Schütze), Main joins the increasingly influential reactionaries who eschew rock’s lessons, the group’s obsession with bumps, clicks, and whirs producing a more organic soundtrack for modernity. This double CD collects six EPs released monthly in the U.K. in the latter part of ’95. Enveloping and exhausting the willing, Hz is a dazzling link in the evolution of ambient and related musics that unfortunately wears itself out on its second disc. Along the way, the album is bewitchingly expansive, its stillness and electric articulations suggesting artificial intelligence with a life of its own. At the same time, its sounds are soothingly animal, as in “Maser”‘s bird caws, cricket din, and murmuring voices. Not so much a collection of compositions, Hz’s movements seem to form one overarching piece, whose recurring themes may seem fragmented, but in the end fall very much into place.