Keshiri, I ended up taking out the 12AT7's and putting back in the stock EH 6922. Based on my limited experience with the Zoe so far, the 6922 tubes seem the way to go. As HP said, it is sort of fun being able to roll different tubes; but in the end I suspect the manufacturer already did this and put the most compatable tube type in the stock units. That said, I received the Amperex PQ USA White labels this week and burned them in a couple of days, then man oh man, what a nice sound. I have owned some pretty expensive gear, but I consistantly find the most expensive or most highly rated stuff is not necessarily what I like best. To me, this Lector set up (CDP 7TL MkIII and Zoe) is just great - very musical, dynamic, clear, quiet and just plain fun to listen to. I am currently running that front end into Cary 500MB monos and my Aerial 9's. I do have a wanted ad for another preamp (Lamm LL2), one I have always wanted to try, but I am not in a huge rush because everything sounds so good right now. Regarding your Zoe, I would stay with a 6922 varient, and personally I like the Amperex. I have used the CCa's Rodman99999 talks about in a SF Line 3 SE I used to own, and they are nice but maybe a touch on the clear/extended/neutral side of things compared to the better Amperex's which are a little more in the rich/organic/full-sounding camp - both have good bass.