OK, I have had them back for 5 days - here is my impression. Before getting these upgraded, I was running the speaker cables through Speltz autoformers to match the 4 ohm speakers to my 16 ohm amp. Those are out of the picture. I don't know if the Triode Masters (love that name) will improve with more breaking in, but they are so good as is that will only be a bonus. As mentioned by another AC member, the treble is better and for some reason, so is the bass. When I used my "powerhouse" amp (30 tube watts) there was little need for a sub on most recordings. I can mute my 2 GR Research dual 12" subs remotely, so it was easy to do this comparison. With my 15 watt Shindo Montille there wasn't quite the deep bass, but this is not an issue with my subs perking along. The sound is gorgeous. It is impossible to quantify, but the biggest improvement is a sense of, for lack of a better word, an organic sound to it all. It just seems to be more effortless and natural (but will never sound like live music, no system does). I have sat mesmerized by the beauty of the sound. There is depth I never had before - probably a result of the rear-firing driver. And it also seems to be more efficient - I have a 2A3 amp being made that I hope will drive them. That's about it - I am not a great review writer. Overall, a bigger improvement than I was hoping for and most highly recommended.