The Seymour Duncan SFX-04 Twin Tube Mayhem™ is a high gain guitar preamp that uses a duet of subminiature 6205 vacuum tubes and is voiced to evoke the heaviest sounds that define metal. The new-old-stock, USA-made Phillips Sylvania® 6205s represent the pinnacle of tube technology. They were designed and manufactured to meet the U.S. Government’s [...]