Determining tube bias....Mesa

Discussion in 'Amps and Cabs' started by hours, Apr 6, 2015.

  1. hours

    hours Member

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    Looking to replace the tubes in my Mesa and trying to figure out what will work..

    I know the simple route is to buy Mesa brand tubes, but I want to try some others.

    How do I determine what tubes will work with the correct bias?

    I need 12xa7 and el84s.


    Thanks!
     
  2. Red Planet

    Red Planet Member

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  3. rollyfoster

    rollyfoster Supporting Member

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    i think you can just contact whatever tube company and tell them you need something in Mesa spec since they have a set bias. AFAIK preamp and possibly el84 should be fine regardless.
     
  4. hours

    hours Member

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    It's a Rocket 440. 4x12xa7 and 4xel84

    I'm trying to order off amazon...
     
  5. riffmeister

    riffmeister Gold Supporting Member

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    12AX7 doesn't require biasing, only power tubes like the EL84, 6V6, 6L6, EL34, etc...
     
  6. Red Planet

    Red Planet Member

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    We need to find out if it's Class or Class AB, I'm not familiar with that particular model. I will see if I can google.
     
  7. Red Planet

    Red Planet Member

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    I couldn't find anything and the manual does not say.
     
  8. Monstercastle

    Monstercastle Supporting Member

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    Doug at Doug’s Tubes can hook you up and give you options based on what you are looking to achieve. He will know the values the tubes need to be in. Alternatively, so will Eurotubes if JJ'S are all you want. And Groove Tubes EL84 in the 4-6 range should be ok too.
     
  9. Red Planet

    Red Planet Member

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    What he said.
     
  10. Valus

    Valus Member

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    Tube Depot can do this as well!
     
  11. hours

    hours Member

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    Thanks for all the recommendations for various tube vendors...and I am sure they all can provide great advice.

    What I want to do is understand the differences in tube biases and how to determine if a tube will work or not....I want to be able to shop around on ebay, amazon, craiglists, etc for different tube and price points? Make sense?

    THanks!
     
  12. Heady Jam Fan

    Heady Jam Fan Member

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    And Eurotubes...

    I get mine from Doug's Tubes for my Mesa, and I've bought from KCANOS for ANOS tubes for my DR.
     
  13. 1moreknob

    1moreknob Supporting Member

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    The best price isn't the best option when buying tubes. Buying from a reputable tube dealer, you're paying a little more for them to have tested the tubes so you most likely won't have a failure. That's why Boogie tubes cost a tad bit more, they test them and burn them in to try to avoid failure.
    Some of the eBay sellers and Amazon sellers, are selling the tubes rejected by companies like the Tube Store etc...


    Sent from my iPad using Tapatalk
     
  14. omahaaudio

    omahaaudio Senior Member

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    Probably better to order from someone that knows how to spec output tubes for your Mesa. Tube Depot is one source, but there are others.
     
  15. Blue Strat

    Blue Strat Member

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    I don't think you'll get a lot of tube tech support there. ;)
     
  16. Blue Strat

    Blue Strat Member

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    It makes sense if low price is the only goal. If the goal is customer service, it doesn't make sense. Most Ebay sellers know nothing about matching tubes let alone what tubes will bias correctly in a Mesa amp.
     
  17. SteveO

    SteveO Member

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    Some things in life simply aren't worth skimping on-primarily tubes, condoms, and toilet paper.
     
  18. Al Rose

    Al Rose Silver Supporting Member

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    There ya go.....

    Al
     
  19. Mutley

    Mutley Supporting Member

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    Blue Strat is right. You should ask him. Mike has helped me out a few times with what will work with my amps.

    No affiliation, just a happy customer.
     
  20. hours

    hours Member

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    And coffee and bed sheets....
     

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