Tungsrams are the best I have tried, better than Telefunken, Siemens, Amperex, Mullard, etc. For new 6922s Electro Harmonix are nice.
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Really, the more important issue is not so much the type of
tube but the damping and tweaking that goes into using the
tube. Start with something like the Electro Harmonix. Ad
a tube anchor from Mapleshade or Hal-o. Ground the tube if
possible and damp the circuit board or area around where
the tube is inserted. It may take a bit of experimentation
but the result is that there is precious little difference
in one type of tube versus the next once these things have
There really isn't a lot to say that doesn't border on generalities to some extent. Hate to be another "it depends on what system and where in the system" poster, but it is true, and often expensive to determine.
If I could suggest only one thing, it would be to find a tube dealer you trust and who knows your equipment, and then TRUST them to steer you to the best tubes available.
In addition, the link provided by Clueless in this thread also points out the variations among brands and designations within brands. This is a widely read link that contains very good baseline information, but may be followed in an overly "biblical" way by some.
For instance, one might think that the pinched waist Amperex are the "holy grail" in this family of tubes, but I can tell you from experience that this is not always the case. The article does not mention that these particular tubes have a high variability in terms of microphonics and are dang hard to match.
I have found that, in general, that the Mullard tubes can usually be characterized by more "warmth" than, say, a Telefunken, but perhaps not always as extended. The very best of the Teles and Siemens are surely very articulate and extended, but sometimes lacking in the midrange, depending on production dates. I have found the Amperex, especially 60's U.S.-made to be very good "overallers" - the white label PQ's besting the earlier Bugle Boys, which are often touted as King.
It is very hard to beat the early-late 60's Teles. IMHO, even the non-gold pin 6dj8's in the line sound head and shoulders above the later 6922 and 7308's which can sound rather dry (I will stick to U.S. designations, here, instead of ECC88, etc.). For Siemens it is a similar situation. A CCa of the 80's cannot hold a candle to a 60's version, generally. BUT, you pay for the pleasure, of course. A great point that "Joe's Tube Lore" alludes to is that many of the earlier tubes can be found under other labels (i.e. HP) at reasonable prices, but ya gotta dig, or rely on your supplier.
Another thing is where in a system the tubes is used. If the placement is in a low gain situation, then the audible difference between tubes will be less noticeable that in a something like a phono stage. It seems kind of strange to me that many will argue over brand and type of tubes when they are using them in something like the output buffer amp of a CD player (a mostly no-gain, non-voltage application) Here, the tube brand is probably one of the least noticeable variables. Others will likely argue this point but, hey, my skin is thick.
So, I would say that the term "rolling" tubes was come by honestly. Often it takes several rolls (as in dice) to come up with a winner. Often the winner is not what you'd expect from looking at the "headliners" and "price lists". For instance, I just parted with a Kora Eclipse, a very fine preamplifier of which I had two other previous versions. It is a triode design based on using three 6922's. I tried various and sundry Teles, Siemens, Amperex, Mullard, and Valvo tubes - and within the brands 6dj8's, 6922's, 7308's, etc. etc. When all was said and done the very BEST sounding tube in that piece, IMHO, is La Radio Technique 7308's. Not a tube that would have appeared on anyone's wish list, not all that easy to find, but a clear winner. Go figure....then, to really give things yet another spin, think about the 6N1P's, 6FQ7's which can SOMETIMES prove to be nice replacement....
Brian, You have enough information here to pretty much answer what I intended to post. Interesting that the link provided to Joe's tube lore is Joe Sanders, a good friend of mine. He and I trade information frequently and I supplied him his Soundlab M1 speakers and Aesthetix Callisto. Obviously we have almost identical taste in equipment, but differ on tube choices.
In general, my preferences for 6922 / 6DJ8 / 7308 are as follows:
Mullard white dot, gold pin 6922
Siemens CCa 6922
Amperex 7308 CEP (US Mil)
Currently manufactured tubes are not good at all (in my opinion). The best sounding of these in 6922 version is the Tungsram, then EH 6922, then Sovtek and (worst) Phillips JAN. Positions change radically with the 12AX7 tube, with Sovtek being first place. Why they can build a decent 12AX7 and not the 6922 is a mystery to me.
As some posters have already stated, tube dampers, associated equipment and circuit design all effect the results of listening and rating the sound of tubes. The order that I have rated is based on my taste and use in the high end equipment that I favor.
One thing not covered here that is important. The sound of any tube changes over time. The currently manufactured Sovtek and EH tubes degrade at an alarmingly high rate. A 12AX7 selected for low noise and smooth bandwidth can degrade to the point of being unusable in as little as three months. Some, including myself, feel this justifies the expense of NOS premium tubes, some of which will last for many years, supplying state of the art performance almost until rendered useless. Somehow the magic of the design and materials of these old stocks have eluded modern manufacturers.
As far as new tubes go generally speaking Tesla's and Svetlana are the comapanies to go with.But because (driver)pre-amp tubes last so much longer it does make sense to invest in NOS.You might get some strong used tubes and compare them to others.If you went with say french Mazda's they would be cheaper than Tele's,Siemans,or Mullards.But this can be a fun thing to try and you wouldn't lose that much by buying and re-selling the ones that aren't used.