I have the same exact amps as you do. Wonderful sounding amps. I installed a set of new production Cetron 845s and a set of new production Western Electric 300B and never looked back. When I first got the amps I bought the SuperTNT 845s but had so many tube failures that I finally gave up and went to the standard bearer. Would I love to have a set of NOS RCA 845s? You bet. Like you said the 211s take 4 so finding four matched RCA NOS 845s that don't end up costing $1000 per tube seemed impossible so I went with the Cetron. I am very happy I did. I never tried the KR. I stopped once I bought the Cetron.
Thank you for your response, Jaiello. Could you please tell me what the sonic difference was between the stock Chinese valves and the Cetrons?
I have the Cary 211AE also. Like you I was curious about the RCA 845s and eventually was lucky enough to find four. The Chinese 845s are great for the money but they sound flat, bright and sterile vs the RCA. The RCA 845s are more 3D, throw a bigger soundstage, life-like midrange, silky treble.
I dont use the RCAs everyday though, only on special occasions. I plan to have the RCAs for my retirement in thirty years. For daily listening the Chinese 845s will do. At this time, you probably wont find four RCA 845s. I would try the Cetron or GE just so you know what they sound like. They do take your amps to another level. Have fun.
If you go with the Chinese tubes..I recommend the Shuguang 845B. Its warmer than the metal plates (845C) and about 90% of their transparency IMO, and less expensive. A very good sounding tube. I agree with Nickt in that they are good enough to listen to on an everyday basis. Super TNT tubes are seemingly sold out till next year, according to their TNT site.
My 211's are 15 months old and I just retubed and replaced the stock Cary tubes. For the 845's, I went with the Shuguang 845B's and I agree with Kehut that they are a nice upgrade over the stock Cary Chinese 845's. These are a very very good everyday tube. I also replaced the 300B's with some EH's, the 6sl7's from Tung-sol and the EL34's from Sino. The amps seem to extend a bit more in both directions and have a lovely midrange with this tube compliment. I am quite happy with the results
I should add that biasing with the Shuguang 845B's is rock steady. I don't get the slow drift I had with the stock 845's.
I have a pair of Shunguang 845b. To me it is not bad at all and worth for the money you pay for.
Thanks for your responses everyone. People who have been using the Shuguang 845B - have you only compared these to the stock Chinese valves on the Cary, or any others?
Nobody tried the KR Audio 845? I've done a search on Audiogon and the only links that come up seem to be about the KR Audio shorting and blowing up the amp ...
I've only compared the 845B's to the original Cary tubes in the 211's. My system gets almost daily use. That means I will probably need to replace tubes every 15 months or so. For me, its a matter of cost/value relationship - for the price, the 845B's are great tubes. Would some NOS RCA's be better? Maybe, but for the price difference, I will be happy with the 845B's.
I'm surprised no one has mentioned the TJ Fullmusic 845's. Beautiful sounding in my Art Audio Carissa Signature. I had the KR's previously, a certain unrelenting and analytical presentation in my setup. I also had issues with reliability as one failed and a replacement was on its way out when I replaced with the Fullmusics, absolutely no reliability issues with these. I have not tried the Shuguangs, however, Joe Fratus at Art Audio stated I would prefer the Fullmusics.
Another vote for 845Bs. I use them in a pair of Cary 805Cs. I've only compared them to the other Chinese 845s (845A and 845C). To me, they are richer, fuller, and more musical than the standard Chinese 845s. Depending on the rest of your system, you might prefer the 845Cs. These are more detailed with deeper, tighter bass, but are also much brighter sounding. If the rest of your system is dark and warm sounding, these might be the way to go.
By the way, you don't state what 300B tubes you are using, but if they aren't Western Electric, I'd make that upgrade first before upgrading the 845s.
Thanks for your responses everyone. Jeffreyds, I have tried tube rolling the 300B's in my system using some borrowed valves and it hasn't made as much of a difference as changing the input tubes or the output tubes. For the time being, changing the 300B's on my amp is on hold because I have found that the output tube makes more of a difference.
I don't have the Cary Amp, but thought I'd mention Sophia Electric as another possibility. I've been using their 300B 2.5v tubes in my Wright Sound Mono 10 amps for a couple of years with very good results. Very reliable and great sound from top to bottom (needed about 100 hours on them though before they opened up). They have 45 tubes as well.