Spider Valve MkII overview featuring Richard Fortus, Isao, and Michael Chavez. Spider Valve™ MkII guitar amplifiers are the best of both worlds. The boutique-style, all-tube designs combine with award-winning modeling to deliver muscular tube tone and unsurpassed sonic flexibility. Spider Valve MkII amplifiers produce unprecedented sonic impact. Get ready for creamy, cascading distortions and enriched tube harmonics that leap from the Celestion® Vintage 30 speakers. The Line 6 modeling flows into the all-tube Bogner-designed 12AX7 preamp and 6L6 power amp sections to produce a guitar-playing experience like no other.