Halve Maen is the ominous double CD from the mysterious Double Leopards. The gatefold case (a smaller replica of the out-of-print LP) is unsettling enough, with a deranged skeleton, a double-take painting on the back cover and a 1,000-megabyte attention-deficit photo collage inside. Wait ’til you hear the inverted orchestral soundwash within. Traditional instruments blend with “your guess is as good as mine” sounds. Are those sleigh bells? Are the occasional drums room-miked? Low-battery video-game tones slide into a murky layer of “Whole Lotta Love” spiraling effects. (You know the part where whirling scrapes mix with Robert Plant’s panting vocals before climbing into the great snare fill?) Holes of swirling headphone buzz deep enough to step in make this amazing effort worthy of eyes-closed, dark-room listening.