Quality problems with Russian 6P3-E power tubes

Discussion in 'Tube Audio' started by BmWr75, May 1, 2010.

  1. BmWr75

    BmWr75 Addicted Member

    Posted this in another thread, but think a new one is merited.

    I bought 8 of these Russian 6P3-Es tubes in recent months from eBay seller basa_79. Never installed them in an amp. Got a tube tester recently and tested all 8. Five were closely matched in GM. Three of them were bad......I could see the wire windings glowly very brightly on two of them and the meter went wild on my tester. One was just dead. I think all three of the bad ones came in the 2nd purchase and were in the original paper tubes. The first quad purchased had no paper tubes.

    Buyer beware with this eBay seller. I've contacted him about the problem, will share the results.
  2. nerdorama

    nerdorama AK member Subscriber

    This is the reason I bought from Jim McShane. I've heard a few stories like this. He takes the hit and culls that bad ones. His price isn't that much higher after shipping from Russia and they're guaranteed.

    Please don't think I'm trying to rub it in. I almost bought from the auction until I heard some of these stories. If I wanted to buy a large quantity and cull them myself, then it may make sense to me. The Russian vendors from whom I've purchased items have all been very good, I just don't want to mess around with tubes that are a crap shoot in a small quantity.

    I hope your seller will work it out with you.

    Jim said in a post that some of his initially bad tubes worked ok after a number of hours of burn-in by just running the heaters to dissipate some internal gas problems. I think that was the story. It might be an answer to some of your bad tubes.

    Jim also suggests that possibly baking them in an oven would clear up some of the gas issues.

    They sound very nice. I've heard them replacing both 5881's and EL34's.

  3. BmWr75

    BmWr75 Addicted Member

    Two of the three bad tubes didn't have any silver flashing inside the top of the tube near the getters. Other than that they looked identical to the good tubes. What does the missing silver flashing mean?

    I've bought from Jim McShane too, he's a good seller. I'll check out the 6CA7s he has.
  4. Pio1980

    Pio1980 AK Member Subscriber

    "What does the missing silver flashing mean?"
    Either they haven't been "gettered", or if a whitish powdery appearance very gassy or no vacuum due to air leak. All very bad and useless tubes.
  5. BmWr75

    BmWr75 Addicted Member

    Here's a picture that shows a tube with the missing silver flashing.
    Last edited: Jun 16, 2015
  6. Ty_Bower

    Ty_Bower Well-Known Member

    The flashing is still there, it has simply turned white from exposure to air. That tube has lost its vacuum and is no longer good. Nothing can be done for it.
  7. Bluelobster

    Bluelobster Well-Known Member

    These Russian tubes are really good once you get a quad that works and is suitably matched. Don't give up on them I think you will like them, certainly better than any 6ca7 out these days. Set them up so that they are about 23 watts output per pair, that seems to be their sweet spot.
    A fellow over at the Asylum, goes by "Twystd" turned me on to them over a year ago. I first put them in an ST70, then Dynaco MKIV and was really impressed and happy.
    BTW the tube with the clear top lost it's vacuum, hence no getter. These tubes have been around unused for years so it may not be the sellers fault unless he said they were checked and tested.
  8. BmWr75

    BmWr75 Addicted Member

    The two tubes that have clear tops had not been tested. They were still sealed in the original paper boxes, rusty staples and all. The other bad one was probably also untested.

    The 5 good ones are pretty well matched. Will give them a go in my ST70.
  9. neon the cat

    neon the cat New Member


    I like this tube, and was turned on to them by Ty Bower (thanks, Ty!).
    A quad I ordered from ebay seller, nixiestore, had one tube DOA (filament).
    Jacob sent a new tube immediately from his Russian warehouse. Trustworthy guy, I will buy all my Russian tubes from him in future.
    Since then, the tubes have been working and sounding very good.

Share This Page