Whats the best and quietest 12AX7 tube

For one thing, Kevin at Upscale is not a terrific dealer guy. He may have a few buddies out there, but I know from personal experience that he doesn't know what he's talking about. David Lewis is the same way. AS FOR YOUR SILWAY MK-2: I've tried some extensively, comparing it to many others, and find that it lacks natural timbre in the upper midrange, and sounds laid back in that range; gives the music an artificially "crystalline" quality. Transient snap in the treble seems a little hyped also, however smooth it is. Bass is very dynamic. If that's what you need to get neutral sound for your system, then I doubt there's anything better out there anywhere near the price. But in my system, whether on headphones and a tube headphone amp, or on a solid state linestage with Krell power amp (and either from vinyl or CD), THE MIT 330 SHOTGUN HAS BEATEN EVERY INTERCONNECT I'VE TRIED UNDER $3000 PER METER...and this is only a $700 interconnect!! GOOD LUCK GETTING TUBES TO GO QUIETER. What solid state preamp convinced you to get into tubes? I'm open minded about tube preamps, but not all solid state ones are cut from the same cloth...All the best.

David, I don't know if I can help, the comments from Drumsgreg are correct in that you should seek advice from Rogue. They know about their product much better than I. As far as Kevin, his advice is excellent, and he is probably not keen on promising a quieter set of tubes for your unit, when every factor is not under his control (or knowledge). I have found him to be accurate on sound of tubes, and totally honest in presenting product that is exactly what he says it is. The Penta people purchase tubes out in the market and resell them, exactly what Kevin does. The big difference is that Kevin tells you what you are buying, and Penta does not. It is difficult to choose (and later replace) tubes if you are not certain about what you got in the first place. My choice for NOS tubes as a replacement for the Penta 6SN7 would be the RCA black plate (same number) or if you can afford it the 5692 Red base RCA military tube. The 5692 is quieter, more linear and less prone to microphonics (Kevin can discuss with you). As far as the Phillips, I am not impressed with them. For the 12AU7, call Antique or Kevin and try the Amperex 7316, or Telefunken 12AU7. Both of these sound different from each other, both are great tubes, but you must listen. On the noise issue in general, ask Rogue if we are missing something here, is this an issue with many owners? What can they suggest as an approach to help you? I would not be afraid to call them and state your case. They may even offer you tubes to see if they can help you resolve this issue. One thing, the Sovtek 12AX7 tubes are generally very quiet, HOWEVER they do vary, unless someone has selected them for quiet, you could get a dog. I would ask the factory for a set that they are sure is "perfect" and if the problem persists, ask them why. If the issue becomes one of sound quality, the other tubes I have named are all better than what you have by a mile.

David, Albert, Carl, et al: try Ned (extremely knowledgeable!) at Triode Electronics, Chicago. Extensive web listing of tubes, including hard-to-finds) and great prices. He's the best of a bunch, IMHO.

I purchased tubes from Ned at Triode as far back as five or six years ago. Yes, Ned does indeed know what he is talking about, but at last discussion, he was unable to provide some of the REALLY rare and hard to find tubes I was purchasing. IE: Telefunken 6922, Genelex KT66, Telefunken 6DJ8. All of these are EXTREMELY hard to find as brand new old stock. In fact, Kevin is the only person I have ever found to have NOS Telefunken 6922 that are the genuine article. If you do not need these tubes, my remarks are a moot point, however my respect for Kevin is in the fact that he has been able to deliver ALL the tubes I want, and at the absolute best quality available.

You've got to test listen for compatibility between various 12AX7s and the other tubes they're sharing space with in the preamp. But, try the Ei Yugo 12AX7. It is very inexpensive, and you might find it has a very musical balance too. It is also as quiet as any 12AX7 I have heard.