Replacing Sovtek 6922 for NOS


I have the Logos, the newest hybrid amplifier from Pathos Acoustics. The original tubes are Sovtek 6922. Any good? I suppose I could get a much better overall sound if I upgrade to NOS tubes within the ECC88/6DJ8 family. Amperex (BBoy) and Mullard seem to be very good. But I really would like to know which are your preferences. Thanks. tgm
lisbon
A good place to begin your research is at Joe's Tube Lore. To get there, go to audioasylum.com, then to FAQ, then scroll to Joe's Tube Lore. My experience has been that the Sovtek 6922 lacks the dynamics, subtle inner detail and imaging of premium NOS tubes like the Siemens CCa/7308 or Amperex 6922PQ/6DJ8 Orange Globe Logo. Even the more modestly priced Amperex Bugle Boy/A Frame, Siemens 6922 w/gold pins and Mullard 6DJ8/6922 will offer much better sonics.
Yes, you have a whole lot of room for improvement over your Sovtek (one of the worst I've heard when comparing to some of the premium tubes that Mrwigglewm mentions). You are in luck that there are many excellent alternatives that were manufactured in that family. My preferences run towards the Siemens CCa's or the Telefunken CCa's. In my applications the former is more detailed and a bit more analytical, while the Tele seemed a bit warmer while sacraficing some detail. As with all tube recommendations (and many others in audio) YMMV. Do be careful in seeking out the premium tubes as there are also many counterfit and relabled tubes in that family. Buy from a reputible dealer and you should be fine. Check the archives here or on AudioAsylum for an abundance of further recommendations (enough to make your head spin) regarding the 6922/6dj8/E88CC family. Good luck.
Hi again Jax2. Yes, it's me again (from Portugal). I have started a new thread for a couple of reasons: first, the title of yesterday's thread was correct afterall (!): the tube family is 6922/6dj8/E88CC (and not ECC82 as I said later). Then, I asked Pathos Acoustics about the original tubes and they are Sovtek 6922. According to my readings (and thanks to you) I found out these are not so good tubes. About Portugal, I am glad you enjoyed my country. You talked about Fado and this would be a loooong conversation. One gold tip: do NOT listen to anyone besides Amália Rodrigues. Amália is what Fado is all about. Trust me.
Hey tgm...I didn't even notice that was you posting!! OK then, you've got even more choices than you imagined now. Plenty of great E88CC(a)'s to choose from and quite abundent as NOS in Europe. Try the Micronetics dealer or dealers in Germany as the German tubes in that family are outstanding. The Mullard (Britain) is good too, but I do like the German better (Mullard gets a bit too warm and starts to sound veiled in my experience and for my taste).

While in Portugal I did obtain a disc of Fado music performed by Maria Teresa de Noronha which is wonderful. Hard to find stuff by her here. I also very much enjoy Madredeus and Misia. On another thread someone strongly suggested I check out another contemporary,Mariza. What do you as a native think of the more contemporary interpretations that are exposing the rest of the world to Fado more than ever before?