Whadda Think Of The BOHLENDER-GRAEBNER 520???

Not sure about the 'strict' power requirement. I run a pair of 420's with a 50 watt YBA Integre without any problems. Most of the time I listen at the volume at 12 oclock position. There is plenty of excess power if I need it. I believe it is the 'quality' of the watts as opposed to the 'number' of watts.

they require a "fast" powerful ss amp so there are limitations , like the electrostats..if you are looking for a great alternative try e-speakers.com..high quality ribbons and other drivers