Tube Rolling 12AX7 - Need Advice/Suggestions


Have a Jolida SJ-502A Tube Integrated who's tube compliment is currently (4) Tung-sol 6550, (2) Tung-sol 12AX7 and (2) NOS RCA 12AT7.

Recently purchased a Jolida JD-100 CDP which currently is using (2) NOS RCA 12AX7. The person I bought the CDP from kindly (thanks Colleen) gave me a stash of some 12AX7 tubes which include pairs of EI Elites 12AX7E ,Gold Series Groove Tubes 12AX7-M, and EH 12AX7.

Right now, the Tung-sol in the amp, and the NOS RCA in the CDP sound good, but wondering what other 12AX7 combinations might sound as good or maybe even better? Anyway, was curious about what some of you more experienced "tube rollers" might think would be the best combination of 12AX7 to be running in the CDP and AMP?

All comment appreciated.
cleaneduphippy
My guess is ( guessing only ) that the tubes you are using are better quality tubes than the tubes you were given..They are new production 12ax7 ( nothing personal ) and probably why they were given to you,due to there modest value..They will certainly work but my guess ( I have tried them myself ) is what your using is better............
Ditto on Thorman's comments. It is doubtful the RCA NOS will be beat by current production, unless you are having microphony or noise with your RCAs.
Of those new production tubes that were given to you the Groove Tubes are the best IMO. Try them in the amp. As previously stated those RCAs will be hard to beat, so keep them in the CDP. Of course a lot depends on whether you are using closely matched pairs.

If I recall my research when I was considering a Jolida CDP a lot people like the black plate 5751s, a lower gain version of the 12AX7. A good source to look up on the Internet is Joe's Tube Lore. There is a whole section of the sound characteristics of 12AX7 and 5651 tubes (others as well). I think in the long run its best if you experiment on your own (with those tubes you have). A lot more fun too. Maybe later you'll decide to try some others.
Brendan Biever of tubeworld.com recommended and sold me some
great 12au7 and 5687 tubes for my preamp/headphone amp.
They made a world of difference from the stock tubes.
Much more liquid and alive and relaxed at the same time.
Well right now, I'm running the NOS RCAs in the CDP, and the EH 12AX7 (switched out the Tung-Sols) in the amp, and it's sounding pretty sweet. This afternoon I've listen to Robbin Ford, Susan Tedeschi, and Tab Benoit, and it sounds the way I want to hear it. Now how the EH 12AX7 might sound with Allison Krauss or Del McCoury might be a differnt story. But for my more blues orientated material the EH is sounding fine. Definely got that "juke joint" sound.