A few months ago I decided to actively biamplify my magnepan 20.1's. While looking at possible amps I accidentally came across the AVAHIFI site. At first, I couldn't believe such (how dare I say it) "reasonably" priced amps could compete with the best. However, all the postings on this site and Audioreview convinced me it's worth taking a chance. I ordered a pair of Ultra 550 about 3 months ago and they finally arrived about 2 weeks ago. I tell anyone considering these amps with the magnepans...JUST DO IT. These amps are truly world class. The bass is not only deep, but it's really fast and tight. The 20.1's are capable of truly extended and airy highs, and these amps provide that in spades. The mids are just plain beautiful and real. From top to bottom the music is balanced and effortless. I swear my Maggies are smiling. Thumbs up
One recommendation is to give these amps room to breathe, they run a bit on the hot side.