Cary Audio SLP-05 question..

There is so many good 6sn7 tubes out there I can't see those being the only ones to float the boat. It may take a few sets but they're out there. Most of the GE 6sn7 tubes I didn't like BUT the bridged filament 6sn7's sure sounded a lot better that the other GE's. To my ears GE had a harsh gritty top end. Now that may be nice for say a guitar amp but for music no. The Pope's were a ladder plate design and that design was old RCA, Raytheon and Sylvania black plate tubes. Later Sylvania used the triangular black plate in the chrome dome design which I always thought sounded pretty darn good.

I never got ears on the Popes myself because if I was going to spend that much I spent it on 5692 tubes.
5692's were all made by one company the red based 5692 is RCA model is the most expensive. I've found that the micanol (brown) based 5692 CBS and Sylvania are fabulous tubes and were a bit cheaper. Be aware that sone folks will try and sell regular 6sn7's as 5692's. In order to be 5692 they must have triple mica and dual getters on top with extra support rods that go through rivets on the plates.

Early CBS parallel T-plates with the bottom getter or bottom foil getter are very very good as well but very hard to get anymore. After about 1956 GE started making all the CBS tubes and quality went down.

Do not let me dissuade from the GE's you may actually find them to your liking.