There might not be a IVb schematic out there in circulation because it is a currently sold amp. I saw someone selling the Mesa tech's schematics disc not too long ago on e-bay. It covered everything. You might try to watch for it to surface again because you might be able to snag one from the seller even though the auctions keep getting flagged and removed. I keep meaning to get the guy an e-mail before he gets shut down. The screenshots look pretty cool. If I could get hold of one I would definitely share the pertinent information with those in need here. I doubt I would ever post the schematics up in respect for Mesa because I would not want them to get ripped off for their designs.
