Brian, You have enough information here to pretty much answer what I intended to post. Interesting that the link provided to Joe's tube lore is Joe Sanders, a good friend of mine. He and I trade information frequently and I supplied him his Soundlab M1 speakers and Aesthetix Callisto. Obviously we have almost identical taste in equipment, but differ on tube choices.
In general, my preferences for 6922 / 6DJ8 / 7308 are as follows:
Telefunken 6DJ8
Mullard white dot, gold pin 6922
Siemens CCa 6922
Amperex 7308 CEP (US Mil)
Currently manufactured tubes are not good at all (in my opinion). The best sounding of these in 6922 version is the Tungsram, then EH 6922, then Sovtek and (worst) Phillips JAN. Positions change radically with the 12AX7 tube, with Sovtek being first place. Why they can build a decent 12AX7 and not the 6922 is a mystery to me.
As some posters have already stated, tube dampers, associated equipment and circuit design all effect the results of listening and rating the sound of tubes. The order that I have rated is based on my taste and use in the high end equipment that I favor.
One thing not covered here that is important. The sound of any tube changes over time. The currently manufactured Sovtek and EH tubes degrade at an alarmingly high rate. A 12AX7 selected for low noise and smooth bandwidth can degrade to the point of being unusable in as little as three months. Some, including myself, feel this justifies the expense of NOS premium tubes, some of which will last for many years, supplying state of the art performance almost until rendered useless. Somehow the magic of the design and materials of these old stocks have eluded modern manufacturers.
