Did you check out this thread?
Hey everyone, I wanted to start a thread about an amp that is very special and likely isn't very well known. I'm lucky enough to own a prototype/custom Bogner amplifier that was used on the recordings of City of Evil, Self Titled, and Diamonds In The Rough. It may have been used on some other...
synner.com
It was posted by my buddy, Alex Cain, (who has since deleted his account). He has the original Bogner that was used on Waking, COE & Self-Titled. I gave him my Hellwin when I left California. He is good friends with Fred (A7X's engineer and co-producer), and is super-knowledgable about what A7X used on each album.