Passive speakers are the best since you can fine tune it with cables internerconnects,speaker cable, what you use under or on the amp,what amp you use,dac........... I feel 50 watt is not enought with dynaudios, go for no less than Marantz PM8005,Nad C356BEE, mabye Cambridge CXA 80, if sound quality is more important then spl mabye try the nad D 3020 (small size,bluetooth,built in dac,good sound, stereophile rates the D 3020 in a very high "soundquality" class)