I do not know what you mean by "powerful", but I really enjoy my Larsen 8 speakers. I had borrowed a pair from my local dealer and my wife actually liked the way they looked! She says that they remind her of plant stands.
http://www.theabsolutesound.com/articles/larsen-model-8-loudspeaker/
http://www.theabsolutesound.com/articles/larsen-model-8-loudspeaker/