I have a bunch of EL34s. EH 6CA7, NOS Sylvania 'Fat Bottle' 6AC7, JJ EL34L, JJ KT77, Sovtek el34C. For 6l6 I have JJ 6l6GC, Mesa Boogie, and Ruby. Yes, I have guitar amps, hence these tubes. Are they fine to try or something NOS or both? Any suggestion welcome.