Need help identifying a tube

Discussion in 'Marshall Amps' started by Emtbreid, Jan 23, 2021.

  1. Emtbreid

    Emtbreid Well-Known Member

    Joined:
    Oct 22, 2018
    Messages:
    678
    Likes Received:
    776
    Location:
    East Coast, USA
    219CF724-B62E-43DB-9BAB-32807BA6C9F7.jpeg 3DC85BFA-C4C5-440D-A4A6-985E14829F5F.jpeg Hi....
    I recently got a really clean 1978 JMP 2104. The guy I bought it from changed all the tubes, and gave me the preamp tubes that were in it. Ones a newer JJ ECC803S, but the other 2 are identical and have no logo. I’m thinking they may be original... can anyone advise? I know the pictures are a bit blurry so I made a short video.
     
  2. StingRay85

    StingRay85 Well-Known Member

    Joined:
    Aug 18, 2019
    Messages:
    1,072
    Likes Received:
    725
    It's a Tungsram made in Hungary :coffee:

    Nice tube, gets good credit in Marshall amps.
    :cheers:
     
  3. Emtbreid

    Emtbreid Well-Known Member

    Joined:
    Oct 22, 2018
    Messages:
    678
    Likes Received:
    776
    Location:
    East Coast, USA
    That’s what I thought. I’ve got two of them... one has a 56 on the foil tag. I’m not sure if they’re any good...
     
    Mitchell Pearrow and Old Punker like this.
  4. StingRay85

    StingRay85 Well-Known Member

    Joined:
    Aug 18, 2019
    Messages:
    1,072
    Likes Received:
    725
    The number at the getter is apparently what identifies it as a Hungary made tube.

    You can also find them with the Haltron branding, and I have one that has the number missing although same construction.

    Only way to really know if they're good is by testing them. My experience is that is 90% of cases the old "vintage" preamp tubes measure as good as new. As long as they are not microphonic, or give hum or noise, you can be sure they'll outperform current production tubes. It's one of my guilty pleasures, buying cheap 60s-70s tube amps and pull out the tubes, exchange for JJ and sell them on.
     
  5. Emtbreid

    Emtbreid Well-Known Member

    Joined:
    Oct 22, 2018
    Messages:
    678
    Likes Received:
    776
    Location:
    East Coast, USA
    Well, this JMP needs bias caps replaced at least, so when I go to the tech I’ll have him test these. Saw the boxes of the new tubes he put into the back of the amp when I bought it but had no idea they had tubes in them. He replaced the two tungsram and the JJ ecc803s with standard JJ ecc83. I’ve already pulled two of them out... put a tung sol 12ax7 in v1 and the ecc803s in v3.
     
    Mitchell Pearrow likes this.
  6. StingRay85

    StingRay85 Well-Known Member

    Joined:
    Aug 18, 2019
    Messages:
    1,072
    Likes Received:
    725
    Put them back in and see what you like best. I would say put them in V1 and V2, and see which tube you like best in the PI
     
  7. Jethro Rocker

    Jethro Rocker Well-Known Member Silver Supporting Member

    Joined:
    Mar 11, 2011
    Messages:
    9,211
    Likes Received:
    12,548
    Location:
    Saskatoon, Canada
    Yeah I agree. Tech doesn't need to test, hard to tell with AX7s. Use em!!
     
    Mitchell Pearrow likes this.
  8. anitoli

    anitoli Well-Known Member Gold Supporting Member

    Joined:
    Jul 9, 2011
    Messages:
    9,229
    Likes Received:
    12,262
    Location:
    Lewiston, Maine U.S.A.
    I have tube testers and i can assure anyone that irregardless of how the tube's test results come out the sound can not be determined by the numbers. The only way to know is to use it in circuit. So my advice to those who may be considering throwing big bucks at old tubes would be to approach this very cautiously.
     
  9. zombiwoof

    zombiwoof New Member

    Joined:
    Nov 27, 2008
    Messages:
    10
    Likes Received:
    0
    I'm not sure why you're saying this, as the OP is just wanting to know what the tubes that were already in his amp were. He wasn't buying old tubes.
    Al
     
  10. Sg-ocaster

    Sg-ocaster Well-Known Member

    Joined:
    Jun 1, 2020
    Messages:
    475
    Likes Received:
    558
    Yup.........I had an old dark at the base high milage I61 mullard in V1 of my 2210 a few years back........Bought a strong testing clear glass pretty I61 as a spare on ebay....and it sounded like poo.
    I buy cheap used on ebay and if I like um.........then I buy spares from KCA Brent Jessee or a couple ebayers I have come to trust.
     
  11. anitoli

    anitoli Well-Known Member Gold Supporting Member

    Joined:
    Jul 9, 2011
    Messages:
    9,229
    Likes Received:
    12,262
    Location:
    Lewiston, Maine U.S.A.
    Cause i felt like it. :D
     

Share This Page