Schematics of stompboxes collected online, backup only Schematics of some amp heads like EVH5150 also included. Forums: freestompboxes.org (Recommended) guitar-gear.ru diystompboxes.com ssguitar.com Websites: generalguitargadgets.com tonepad.com homemade-circuits.com aionelectronics.com blueguitar.org madbeanpedals.com ampage.org muzique.com geofex.com sabrotone.com electricdruid.net guitarfx.it