Purple/UV glow in 12AX7

Discussion in 'The Workbench' started by JM5010, Sep 30, 2019.

  1. JM5010

    JM5010 Member

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    This tube was working fine yesterday. It’s an Electro Harmonix 12AX7. This glow isn’t normal at all right? It makes a scratching/sizzle sound when the standby is turned on. The tube warms up like normal too.


    2D623904-0703-4981-A6E4-ABFD3303082B.jpeg
     
  2. JM5010

    JM5010 Member

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    Also, i swapped the tubes around to see if something wrong with sockets. All my preamp tubes and sockets are fine, it’s just this little guy that’s glowing purple.
     
  3. ampmadscientist

    ampmadscientist Well-Known Member

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    The tube seems to be bad. Purple is not normal for a preamp tube.
     
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  4. mickeydg5

    mickeydg5 Well-Known Member VIP Member

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    Purple indicates vacuum leak/gassy tube unless you went to the auto parts store, bought and installed some of them LED night lights.
     
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  5. Trapland

    Trapland Well-Known Member

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    Pimpin’

    Sell it on eBay for triple.
     
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  6. ampmadscientist

    ampmadscientist Well-Known Member

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    It's RARE! it's vintage 2018, and it's NOS now. Got to be worth $399.00.
    + I love purple. (soon to be legendary)
     
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  7. myersbw

    myersbw Well-Known Member

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    Mount it sideways behind a clear lamp jewel and call it the magic eye! :p
     
  8. South Park

    South Park Well-Known Member

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    I had slo 50 clone that the el34s would flash blue when you hit the stand by for a second.change out tube and see what happens and try it in a different amp
     
  9. Adieu

    Adieu Well-Known Member

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    Alas

    Even if it does look so much cooler
     
  10. LRT#1

    LRT#1 Well-Known Member

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    Had a 5881 that glowed blue purple swirls. Look cool but sounded like ass
    Bad tube
     
  11. anitoli

    anitoli Well-Known Member

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    Purple Haze, that tube was played by Jimi.................
     
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  12. Fender

    Fender Active Member

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    it's normal on EL34 to have a blue glow guys, don't mix preamp tubes and power tubes
    this 12AX7/ECC83 should not have this cool color
     
  13. JM5010

    JM5010 Member

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    I’m selling it for $500 on ebay, NOS indeed. Was used in Hendrix’ main amp!
     
  14. JM5010

    JM5010 Member

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    So far i’ve had to replace V1, and now V2. Next thing you know V3 dies and i need to replace just minutes before i gotta get it shipped....
     
  15. ampmadscientist

    ampmadscientist Well-Known Member

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    Start the reactor... Free Mars!
    There actually is a magic eye tube 6E5C.
    [​IMG]
     
  16. myersbw

    myersbw Well-Known Member

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    Yup! I have one somewhere in the shop...need to dig it out!
     
  17. Matthews Guitars

    Matthews Guitars Well-Known Member

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    I've never seen a PREAMP tube do that before! It may sound bad but it'd have a place in some piece of gear that I was running on display. Pretty!
     

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