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Is upgrading stock tubes standard proceedure?

I'm just wondering if I'm the last guy to realize just how enormous an improvement can be had by upgrading stock tubes to NOS. Most of my system has been in place for some time now and I've sought to improve it's performance by tweaking. Tube changes have resulted in noticeable but subtle results; most of the time involving trade-offs... until now. I just upgraded the 6922s in my cj Premier 17LS to Amperex 6DJ8s with stunning results. I can't find any trade-offs, everything desirable in audio is improved IMHO. This is the kind of improvement I would have been looking for if I bought a new preamp and spent twice the money. As much as I've read about tube rolling, based on what I'm experiencing now, there isn't enough emphasis, especially by professional reviewers.

So, I guess my purpose in writing this thread is two fold:

1) Why don't tubes receive at least the same attention as the equipment they're in.

2) Just a heads-up in case there is anyone else out there who thinks they can't justify $100 or more for a small tube.
phaelon
tvad
9,467 posts
 
I don't think you can blame dealers for not recommending NOS tubes. Dealers need to be able to offer products that are in ready supply, and that are consistent in their performance. NOS tubes are neither. It's why manufacturers supply only new production tubes. There simply isn't a sufficient supply of reliable NOS tubes.

NOS tubes are quickly becoming extinct. Available to only deep-pocket audiophiles.

Fortunately, there are companies that make excellent use of new production tubes. VAC, ARC, Conrad Johnson and Atma-Sphere come immediately to mind.
mrtennis
3,295 posts
 
many current-production tube components have circuits which are not tube sensitive. i have encountered many examples of this phenomenon. in such cases, replacing stock tubes is not beneficial.
jaffeassc
166 posts
 
I own a CJ CT6 and have also found that there is a significant improvement by changing the stock tubes. I have tried both Amperex and Siemens with excellent results. It’s also interesting to note that in the CJ Owner’s Manual under Vacuum Tube Replacement they make the following statement when speaking of the stock tubes supplied with the unit.

“We know of no vacuum tubes available which will improve the sonic performance of your CT.”

Just not so, IMO
sugarbrie
3,854 posts
 
Gear makers need to have consistency. Every unit they sell should sound the same. So they are going to use a tube that there is an ample supply available. Conrad Johnson does use good tubes and they make an effort to test and match them. There is nothing wrong with using the stock tubes. If you ruin your brand new $5,000 - $10,000 piece of gear fiddling inside the case, you can forget about the factory warranty.

The biggest variation in sound is with simple tube gear. There is not a lot of circuitry, so in many cases you are actually listening to the tube itself. In more complex gear, changing tubes is more of a tweek.

Changing tubes will definitely make it sound different. Better is in the ears of the beholder. Since there will be no agreement on which brand of NOS tube is better for any particular piece of gear, then it really comes down to personal taste.

Once I find a brand of tube I like for a particular piece of gear, I almost never change which tube I use after that. Some people like to tinker.
phaelon OP
1,038 posts
 
Assuming that high quality tube design is not a lost art, perhaps they're just not profitable to manufacture at this time, given the current supply of NOS tubes they would be competing with. Forgive me for seeking the silver lining, but man, I don't want to go back.
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