This is a West German Winston PA/instrument amp.
Pix from this auction:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=006&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=160055099480&rd=1&rd=1
I have one. I stripped it and it has sat arund in various parts of the garage for some years now. I'm gonna pull it out and play some Marshall/Tweed games with it. Two preamps, switching, nothing complicated. Problem is, this amp has a B+ winding of 425VAC and no center tap. That means that it is designed to be used with a bridge rectifier. 425VAC X 1.414 = 600VDC on the plates of 4 EL34s. Teslas can take that, but it makes for a stiff amp. The primary has multiple windings, but is designed to be either 110 or 130 for the lower voltage markets. Using the 110 taps will make things worse, as US voltage is now centered at 117. I'll try the 130 config on 120 and if the filaments don't go below 6VAC I'll try that. Unfortunately I don't have another power trans to use.
Stay tuned.
I'll add that to my threat collection.
-- Harry Callahan (from "Dirty Harry")
