Hello, I can only comment on the Kef Ref. 2 in my room. I would second many of the comments here. With a 60 watt integrated I can reach incredible sound levels in a 12x19 room. Dynamics and imaging are excellent. But the strength, IMHO, is the superb vocals and midrange. Music recorded with some depth and atmosphere absolutely make the speakers disappear. Keep these speakers away from walls and corners to help control the bass unless, of course, you love wild amounts of low frequencies. Added bonus is that the Reference line is magnetically shielded in case you must place them next to or near a TV monitor. Since the Ref. 4 has even greater potential for bass response, seriously consider an amp, tube or solid state, that has a reputation for clamping down on bass control. The sound you get should be tremendous!