Mesa Single Rectifier - Burnt Resistors in V1 Preamp Stage

Discussion in 'Other Amps' started by Engine09, Sep 6, 2015.

  1. ampmadscientist

    ampmadscientist Well-Known Member

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    Don't worry Dan, your time will come.

    See that?
    [​IMG]

    It's not a theory, it's reality.
     
  2. Blackeyes

    Blackeyes New Member

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    Not really, I have a good friend with the same amp that had the same problem and all he ever did was play through it. Amp had never been touched internally. Resistor burned up and scarred the board, what wrong thing was being done?
     
  3. charveldan

    charveldan Well-Known Member

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    Like im suppose to know that ? IDK you or your friend.
     
  4. charveldan

    charveldan Well-Known Member

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    [​IMG]
    [​IMG]

    [​IMG]


    I burned up the 8 ohm tap on a JMP in 1982 hardwiring the fuse while running the wrong wattage speaker cab. I don't recommend that. As for "your time will come" your hollow threats make you sound like my Mom or something.
    My MESA is 18 plus years old & in perfect condition. It would have already burnt up the weakest link if it were going to happen but i'll be sure to let you know if it does.
     
  5. Blackeyes

    Blackeyes New Member

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    That was my point....
    You said to madampscientist "You only have a problem when you burn something up doing the wrong thing"
    That implies something was done improperly and caused a failure, no?
    All he (my buddy who had the exact same issue) ever did was play the amp, you implied the failure was bound to be something done wrong, I'm asking you what wrong thing was being done?
     
  6. BowerR64

    BowerR64 Well-Known Member

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    Pushing the front end to hard?
     
  7. Durden

    Durden Well-Known Member

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    20a fuse instead of a 2.5a seems legit as to cause, no? Bad Tube was the start of it ,no?
     
  8. Dogs of Doom

    Dogs of Doom Moderator Staff Member

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    using the amp... :)...
     
  9. charveldan

    charveldan Well-Known Member

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    I think you're confused. My response wasn't directed at you or your buddy.
     
  10. Blackeyes

    Blackeyes New Member

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    Sigh.....
    Yes, I know that, it was directed at MAS. My buddy had the same problem on the same amp. You told MAS that you'll only have a problem when you burn something up doing the wrong thing, I'm asking what you think was done that was wrong?
    Jeesh, this is tiring..
     
  11. charveldan

    charveldan Well-Known Member

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    No wasn't directed at him or anyone here.

    My comment is if *** ANYONE RANDOM ON THE PLANET is using an amp in an IMPROPER WAY you can damage the amp. IE : Improper load, wrong speaker wattage, using an instrument cable as a speaker cable ect.

    Stop taking things personal it aint about you.
     
  12. Blackeyes

    Blackeyes New Member

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    It never was, I was just wanting clarification. I had no idea it would take days :wallbash:
     
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  13. BowerR64

    BowerR64 Well-Known Member

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    So i never did catch the fix for this problem.

    Just replace the resistors and fix the traces on the board or is there a for sure fix for this issue?

    I read in the post i made AMS said raise the resistors up off the board a little?
     
  14. ampmadscientist

    ampmadscientist Well-Known Member

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    The same thing happens w/ many boogie amps. I have seen this happen many many times.

    The problem is defective factory insulation and design.
    This is a design defect.
    Not abuse.
    No, this does not happen because of mis-using the amplifier...has nothing to do w/ speaker or overloading the input.

    This is very similar to a DSL board defect.

    Then after it shorts, people put in an over-sized fuse and keep playing it. That obviously makes it worse.

    You can fix it but you have to take the board out (bypass the bad spots) and it's a lot of time. You need to have the right tools and the know-how.
    But many of them have been fixed, and can be played again.

    Just as I said before: Boogie amps have just as many problems as any other amps.
    The problems like this happen in humid climates:
    you will see this happen more in Huston, Honolulu, New Orleans, anywhere that the humidity is higher....near the ocean.
    Now you see it for yourself.
     
  15. charveldan

    charveldan Well-Known Member

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    Ive not heard of these mysterious Seaside Communal amp problems you speak of. Heard plenty of new & old DSL problems tho. You may be over-thinking it a bit.
    You got facts/data/links to back that up ?
    Im on the Boogie Board, haven't heard it there either.
     
  16. Blackeyes

    Blackeyes New Member

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    Actually, there's a thread on the boogie board about the exact same problem right now...
     
  17. charveldan

    charveldan Well-Known Member

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    MESA amps are Awesome.

    Not changing my opinion. If you take care of your gear it should last a lifetime.
     
  18. texhex

    texhex Active Member

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    This had me laughing out loud for a good 5 minutes. All these poor dudes down by the seaside with their amps shorting out randomly. LOL The poor bastards.

    Seriously though a 20a fuse in a 2.5a socket.. "Penny in the fuse box" ring any bells?
     
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  19. ampmadscientist

    ampmadscientist Well-Known Member

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    Mesa amps have a lot of problems in humidity.
     
  20. texhex

    texhex Active Member

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    I believe you. I've seen firsthand what humidity can do to electronics and it can be the damnedest thing to troubleshoot.
     

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