I use two different amps. (2nd one first) a pair of vintage/upgraded Heathkit A-9C integrated monoblocks with 20 wpc in a 17x18x11 room with carpeting. The one o'clock volume position is as loud as I can stand it. This is plenty of tube power for loud listening (and for insane listening...well...hard to say).
(1st amp) Forte 4a, Class A, with 50 wpc (and a LARGE power supply), same room. The 11 o'clock position is often louder than I can stand it. Preamp is an AVA modified PAS 3. This setup could produce insane levels quite readily and without effort.
What I discovered about amps powering Europa's is that I could not stand any amp with even a slight edge in the sound. It was TOO obvious and painful. Thus quality is so much more important than quantity (in my opinion). So, with Europa's, amp "rolling" could be an issue (and I say this after comparing notes with another Europa owner). Also, with the Europa's, clarity is so fine that I prefer normal listening set not quite as loud as I would have thought at first.
Great speakers.
