Manley Massive Passive is a 2-channel, 4-band Vacuum Tube Equalizer, featuring a passive tone-shaping portion of the equalizer design and using only the best components, for its ultimately huge, high-headroom performance. The Massive Passive is packed with five highpass filters and four lowpass filters, and you can bypass either or both. The filters are steep, so you can pull out the junk without touching the real music. Its also great-sounding when combined with other bands. Ultimately, Manley went for whats useful when designing the Massive Passive, not whats standard - its a welcome design departure that produces seriously massive results. Features All-Passive tone sculpting circuitry Unique Shelf curves use the bandwidth control Overlapping and Interleaved Frequency choices Every band switchable to shelf or bell Vacuum tube make-up gain and line drivers Parallel symmetrical