Standing at 3U tall and weighing over 20 pounds, the Manley Labs Massive Passive has long been a contender for heavyweight champion of studio EQs with a firm history in recording studios and mastering rooms, and an impressive list of high-profile users. This four-band behemoth takes tone control to a new dimension with each band switchable between peak/dip and bell/shelf for equalization curves not possible with any other analog box.