Discussion in 'Amps and Cabs [BG]' started by TCollins, Oct 20, 2000.

  1. TCollins


    Apr 4, 2000
    I have a Mesa Boogie Basis M-2000 that won't stop making what appears to be tube related noises (crackling). The problem is definitely on the tube side of this "hybrid type amp". Mesa has been very generous in sending me replacement tubes (about 7 so far). The tubes are all Mesa stamped. Is it possible for so many tubes to be defective? BTW, this amp does not crackle & pop all the time--just when I think my problems are over, it starts up again. I'm considering getting rid of what I thought would be one of the ultimate bass amps :(
  2. Sad to hear my friend! I would consider sending it back to them for a replace unit. After all it is a fairly expensive amp, and im sure they will replace it for you.
  3. pkr2


    Apr 28, 2000
    coastal N.C.

    T.C.: I suppose anything is possible but seven bad tubes in a row seems highly unlikely.

    What you are describing sounds more like a bad tube socket. It could be as simple to repair as just cleaning the socket with contact cleaner.

    Tube sockets are notorious (sp?) for losing the tension on the individual pin sockets. An experienced tech can sometimes retension the socket but it's muhh better to replace the whole socket. They aren't very expensive.

    I'm not familiar with your amp, but if the socket is mounted on a printed circuit board, cracked solder joints at the socket are VERY common.

    I don't mean to shout. Just making one point very, very clear. THERE ARE VOLTAGES IN THAT SUCKER THAT WILL LIGHT YOU UP LIKE A PEPSI SIGN. I mean , YOU CAN GET KILLED if you are dumb. inexperienced or careless.

    Believe it or not, as simple as relacing a tube may seem, there is a right and wrong way of doing it. Although not absolutely mandatory, it's best to lube the socket with contact cleaner before you try to remove the tube. after giving the cleaner/lube a minute or two to soak in, grasp the tube near the top and rock the tube in a circular motion as you lift the tube from the socket. too much rocking and the pin sockets will become stretched causing all kinds of grief. Gently and delicately is the name of the game.

    Hope this helps. Pkr2
  4. Doug


    Apr 5, 2000
    Buffalo, N.Y.
    If you're replacing 12AX7 tubes, I'd suggest getting some good NOS(GE or Sylvania) tubes or tubes made by Tesla/JJ Electronics or Sovtek. I believe the 12AX7 tubes Mesa uses are Chinese, which are crap IMO. These are cheap enough to buy and swap out yourself. If your'e still having problems, then take it back, if under warranty, or take it to a good tech, if not.
    Be sure your'e unplugged when servicing.