Zwengel Amplifiers were based at 1136 Margaret Drive; Princeton, IL.

“Zwengel amps started out as Summit Amp Repair in 1993…In ’96 I finally got on “the net” and began doing mods and repairs nationally. At that point I renamed myself Summit Amplifiers. This is where The Banshee comes it. I started getting a LOT of requests for high gain sleeper mods for Fender Bassman and Showman amps which were dirt cheap at the time…. By mid-’01 I was pretty much ready for production. I became a member of NAMM and had my first show this time last year. Well, there’s another company in existence called Summit Audio and they had a **** fit. I was blessed with a cease and desist order and was forced to rename my company and completely reorganize. So now I’m Zwengel Amplifiers.” [Source: Carl Zwengel 2002, Vintage Amps Forum]

Wayback Machine Website was around from about 2001 to 2004.

see Summit ampsZwengel amp head