Awsome amp! Designed in Germany and built like a German tank! Very smooth and neutral sounding. Has a nice kick in the low end - which made it pair very well with my DT-880s.
Had this amp for ~3 years and is in immaculate condition.
For specs, see: http://www.meier-audio.homepage.t-online.de/jazz.htm. (The jazz is the swing, just rebadged).
If you have any questions: please ask!