Looking for thoughts/opinions on tube seller's response to my question...


Hi All!

I recently bought 4 balanced and matched reissue Tung Sol 6SN7GTB preamp tubes from a guy that I've bought 3 different sets of tubes from in the past (with no previous issue). 

I rolled out the early Russian tubes that came with my Schitt Freya and rolled in the new Tung Sols.  Immediately in system idle there is more noise in the form of hiss, scratchy air, etc.  I ran the Tong Sols for maybe 15 hours or so. No change. 

I emailed the seller to which he responded: 

The 6SN7GTB can take a break in period in some applications. If you Google you will see this phenomena is common. Run them in your equipment for 24 houts and re-evaluate. New ones I exchange would have the same break-in period. The factory has indicated it has to do with the cathode coatings used to extend tube life. No problem returning them if the problem persists.

Have you heard of cathode coatings causing this issue?  While I generally like NOS tubes a bit better than reissues, I've never had a new noisy reissue tube.  Also, I really do like purchasing tubes from better stocked places like Upscale Audio because this issue never seems a problem. But when it comes to new reissues, I don't look first to Upscale.  Maybe I should? 

I'm running them in to see what happens.  I'm not optimistic though. 


128x128jbhiller
Check out vintage tube services; the guy rates his tubes in four categories from line to moving coil. And stay away from current production Russian and Chinese stuff; you will be better off buying NOS as they sound much better and last much longer. I never could understand why someone will pay hundreds or thousands of bucks for equipment and then use the junk tubes it came with or think they're upgrading by buying more of the same.
I agree with  bsmg.   ie: You might consider contacting the following, regarding the, " 6SN7GT Sylvania, triangular blackplate clearglass, bottom-getter, medium glass envelope, "Bad Boy"type.MATCHED PAIR" tubes that he has listed on this page:  http://www.audiotubes.com/6sn7.htm  They won't break the bank and have a wonderful, clean sound.  The bottom-gettered, 1940's, Ken-Rad VT-231 is another very nice tube.    I'm certain, Brent could find you a very quiet pair of either.  Their sound is close to the Tung-Sol, Round Plate, JAN CTL and/or Sylvania 6SN7W(metal base), that some of us are paying so damned much for.