Atc are very amp finicky, just so you know. That's probably why people go with the active versions. I personally enjoyed the harbeth sound more with my mc452 in comparison to the atc19 with Mac. That said, I just couldn't justify pulling the trigger on the 19scms unless I was starting off from scratch. It was approximately 2000. dollars more in price and it wasn't necessarily better just different. If I did go atc, I would go actives and save money on not needing an amp. Plus you won't need to worry about amp pairing and wondering if you're optimizing these speakers. That's just my opinion. I also prefer solid state gear with both speakers. I did try a tube with my Harbeths and they were dull. The details came alive more than ever, when I added a SS preamp c52. It was crazy the difference imho.