tube suggestions for cj MV50?

My C-J was the MV-55, but close enough. I much preferred the Svet's sonically over the Sovteks, and had no reliability problems with either. The Teslas sounded better than the Sovteks, though not as good as the Svet's, but I did have repeated reliability problems with them, although their higher-rated "E34L" version seemed a bit better in that regard. I have not tried the EI's, but believe C-J only rates the Russian tubes as being acceptable for this circuit from a capacities standpoint. I would give the Svet's another chance before switching - there was no area of sonic performance that I thought either of the other tubes bettered them in, and I think they generally make a very durable tube.

I have had Siemens, Sovteks, Tesla JJs and Svetlanas in my MV-50. The Svets are my favorites with there nice sweet mid-range. The Teslas are good as well. Not as nice in the mids as the Svetlanas. A little better bass. My experience with Svets mirror Enzo in reliability. Currently have nearly 2 years on a quad set with no problems. If money is no problem, NOS Mullards are clearly the way to go but the Svetlanas are the next best thing.

Anything is an upgrade from Sovtek. I am surprised that Svetlanas burned out so soon. My current set get used about 10 hours a week and is 3 years old. They still test over 85%. The Svetlanas were designed to copy Mullard. If you liked the sound but want a little better quality, spend the dough on NOS Mullards!
Did all of the Svetlanas fail or just one? Get them tested?

Violaguy;

I have had a MV-50 for a number of years. I also had reliability problems with Svetlana.
I bought some used Mullard EL34's abaout 1 1/2 years ago and never looked back. They have way more bass than the Svetlana in my system. You can pay alot for NOS Mullards, but I bought used (a pair here, a pair there)for maybe $125-$150 for a quad.
Good luck.