I was recently in Vienna on a 3 week tour of Europe and I had a Mark Bass amp from the US that…read moreneeded a transformer. I was lucky enough to find an electronics store near my hotel & they were selling a transformer. It was rather bulky & heavy so the salesman said that I should go to a music store named Klangfarbe. I took the subway to this music store & when I arrived I asked one of their employees if they could sell me a transformer hopefully that wasn't too heavy. He said he'd check with his technician to see what they could do. To my surprise they called Mark Bass which is headquartered in Italy & got instructions on how to open up the amp & manipulate the wiring so that it worked in Europe. They also showed me how to put it back to the original wiring once I was back in the USA. All of this @ no charge to me so I thought what a great store. Later I thought why couldn't Mark Bass not have given me instructions on how to do that. Most amps nowadays have a switch for the change in electric current between Europe & North America. I'm eternally grateful to Klangfarbe for their help & kindness & I highly recommend them to all musicians traveling or that live in Vienna.