I agree the Aragon 4004MkII is a great amp for these. However I accidentally discovered that a 35 year old Yamaha CA-1010 gives the Stages the timbre and texture acoustic instruments deserve! At only 90W (8Ohm), 120W (4Ohm) can drive the Stages pretty loud (if the recording is compressed enough) and to a nice level in a lively room if it's a really good recording. The stereo imaging and detail is the best I've heard out of the Stages, and I've had my pair 20 years. I would say that you must be careful not to have too much power or you will end up rebuilding your ribbons. Keep it under 150W 4ohm with a high current amp.
The only other amp I've tried was my ARC D125 (115W). Sadly, this very transparent amp I'd didn't do anything for the potential these speakers possess.
The only other amp I've tried was my ARC D125 (115W). Sadly, this very transparent amp I'd didn't do anything for the potential these speakers possess.