Akkadict, its been three years since I had the 2.3s in my room, and the pair I listened to had the original coax. From what I recall the 2.4 is fuller sounding, and actually sounds like a larger speaker. I think partly due to the fuller and more extended bass, and the fact that the soundstage is both broader and deeper. The soundstage on the 2.3s stayed pretty much between the speakers when driven by Bryston 7B monos. The midrange on the 2.4 is meatier, more tangible, and blends evenly with the highs and lows. The 2.4 doesn't have any of the leaness that I recall the 2.3 had in the mids on up. The upgraded 2.3 coax may have addressed this to some degree. The 2.4's bass is solid to below 30hz in my room, and has a tactile quality that clearly delineates notes and the pitch of different instruments. One other important difference is that the 2.4 appears to be easier to drive. My Plinius SA-102 can drive them hard with good control across the spectrum. That's not to say the 2.4s won't respond to more power, but I think its safe to say the 2.4 doesn't require the same muscle the 2.3 does for good results. The manual indicates they're rated to 400 watts @ 4 ohms output.
I've listened to the 2 2s, but to long ago to comment.
