CJ Premier 15 & 17LS Tube Suggestions


I have been using a conrad-johnson premier 15 phono preamp for about 18 months and just purchased the premier 17LS preamp six months ago. I am very happy with this pair except for what I consider to be excessive tube noise from the stock tubes. With the 17LS set to mid-range (50 on the display), I hear, what I think is excessive tube noise for units at this price range. I haven't had time yet to experiment (too much travel) with different tubes. I am looking for suggestions for low noise tubes (and sources of tubes) that would improve upon the stock tubes I am currently using. Any suggestions for different brands of tubes and where I can get them would be greatly appreciated. Thanks in advance for the help!
Ag insider logo xs@2xcjlundgren
Thanks for your info Groundsource. I have replaced all the tubes in my premier 17LS and 15 with NOS tubes from Kevin at Upscale Audio. The 17LS tubes are quality Sovtek 6922's (not the same as the stock Sovtek's that are included with the 17LS). This made a HUGE improvement in the sound of my system. I replaced the premier 15 tubes with GE long-plate 12AX7's and Mullard 6GK5's. This made an even better improvement in the sound (for vinyl). The nosie problem that I noted in my original post is GONE. The background in now dead silent - even on vinyl. My recommendation - contact Kevin at Upscale Audio. He knows what he is talking about. He know tubes. Trust his judgment. The tubes he suggested for me made all the difference in improving the sound of my system over the stock tubes. Happy Listening!
Hi ,

Its been a long time since your question but I just got a used 17Ls and love it. I hae the stock 6922 tubes and have no tube sound at all. I do have the solid state MF 2500A amp however. Maybe Knut at CJ would send you another set of tubes incase the original ones were bad?? Did you come across any good info or find anything better? I would like to know as I just got mine and would like to try someting new if it si better.

Jim
Ditto, Pops. Mullards put the 14 at a level I feel only the 16LS can beat. Our 14LS is running selected, matched pairs and was compared--at length--with the 6922/17LS. It was no contest. With gain at 99, you have to have your ear next to the Avalons to hear any tube noise. Mullards are far superior to GE, Sylvania or any other 6GK5, all of which I tried. I also found Sovtek 6922s weren't the answer in another preamp. They're undoubtedly used widely because they're readily available, quite reliable and cheap and, in many applications, apparently provide acceptable response. As for milspec examples, of which there are three or four grades priced accordingly, I have no direct experience, so can't say all 6922s are undesirable.
Different preamp, but I have the premier 14 and replaced stock 6GK5's with Mullards and the improvement is not subtle. Much sweeter, more bass, richer midrange. The 14 is absolutely quiet with both types of tubes.
I replaced Sovtecs with so called Russian military grade tubes on 17LS with no great improvment. I recently replaced those with Mullards. Serious improvment there. Much clearer, sweeter & more dynamic. The others sounded quite flat by comparison.
I have a 17LS, and with the stock Sovtek 6922's its dead quiet at all volume levels. If you also have Sovtek's, its likely that one or more of those little guys is having a problem, or that the noise is coming either from the 15, or from somewhere else in the chain.

-- Ken