I have one, serial SP446, late 80's, I want to say it's an 88 or 89, but I'd have to take the cover off to confirm. It has an AllegroSound Vintage NOS tube in there along with JJ's. The tube alone cost $100.00!
No issues at all with it, only reason I would sell this preamp is because I have a Mesa Quad and I don't really need the Studio Pre. Very minor rack rash. I'm asking $535.00 plus shipping.
