@jambaj0e you may want to PM
@Jason Stoddard and see what he says. The 6sn7 equivalent tube challenge has nothing to do with my company, it is just something I came up with to see how much difference folks could detect in such tubes, as well as to find out which ones people preferred. It is pretty easy to go by public opinion or spend $250 for a tube and have a preconceived notion it will be wonderful.
I will be shipping the concealed tubes to Jason along with tube extenders and possibly switch boxes with cables so people can A/B test the tubes. Jason does a monthly get together and the next one will take place September 12 as I recall and feature these tubes. I have sealed them in such a way that it is not likely anyone can tell one from another.
Within the PVC are classic examples of great tubes by RCA, Tung Sol, CBS/Hytron, Sylvania, Melz, Foton, Westinghouse, etc. I need to look around the shop but I believe I can send switch boxes that would allow switching between four tubes at once if Jason can dedicate four Lry 3's to the test process. This will be much easier than what
@bcowen went through. He had to listen to one at a time and just go from memory and he did remarkably well.