Popping/Crackling

Discussion in 'General Electronics Chat' started by mdr40z, Jan 9, 2009.

  1. mdr40z

    Thread Starter New Member

    Jan 9, 2009
    3
    0
    First post newbie....

    I've got a Genz-Benz Black Pearl 30 watt tube amp that just started a real annoying (impossible) cracking and popping. This happens even with the volume off and even with nothing plugged in, the speaker cable is fine, it also happens at all power switching settings, diode, triode etc. It is a 7/15/30 watt amp.
    What the heck? It's maybe 5 years old, does it need rebuilt already? Help....
     
  2. mik3

    Senior Member

    Feb 4, 2008
    4,846
    63
    Why did you get such an amplifier and not one made of silicon transistors?
     
  3. mdr40z

    Thread Starter New Member

    Jan 9, 2009
    3
    0
    I really like the tube tone for guitar... and it has been a great amp

     
  4. mik3

    Senior Member

    Feb 4, 2008
    4,846
    63
    Really? What is the difference compared to the tone of a solid state (silicon transistors) amplifier?
    As for the question I can't help you, I have never used tubes.
     
  5. mdr40z

    Thread Starter New Member

    Jan 9, 2009
    3
    0
    There is a lot more warmth in the tone and less of a bite, and of course there is also growl/mojo at higher output levels that you just can't get solid state
     
  6. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Tube amps are great. But opinions and questions of types of amps really aren't the question here; it's trying to help our OP solve their current dilemma.

    You might be experiencing noise from poor connections in the 1/4" phono plugs. Try using some "tuner cleaner" on both your phono plugs and jacks - but be careful that you do NOT use it on the amp's jacks unless the amp has been powered down for at least one hour, and don't power it up for at least 1/2 hour afterwards.

    A very long-time buddy of mine has performed as a solo musician and in a duo; he religiously sprays both his phono jacks and plugs with tuner cleaner during his setup time; he very seldom has any problems during sound checks.

    Your volume control pot or other control pots may also have "crud" in them; don't be afraid to spray a good bit of tuner cleaner on the shafts and turn them back and fourth several times. The tuner cleaner will both cause the gunk to get washed away, and leave a thin film of lubricant at the same time.

    You must perform this maintenance with the amp cold, however - otherwise, you will stress (or shatter) the glass envelope(s) of the tubes (UK'ers call them "valves"). You really don't want to replace them any earlier than necessary.

    If you cannot find tuner cleaner in a spray can, you might try using isopropyl alcohol, 91% or higher concentration. Don't use the 70%; it has too much water in it.
     
  7. floomdoggle

    Senior Member

    Sep 1, 2008
    217
    2
    You've got a blown or loose tube.
    Dan
     
  8. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
    2,039
    287
    The first thing to to is spritz all the sockets with contact cleaner, and reinsert and remove the tubes several times. If that doesn't fix it, you could have an intermittent short in a tube, or a leaky capacitor.

    If you wiggle the low-level tubes around, do you get any crunching sounds?

    eric
     
  9. flat5

    Active Member

    Nov 13, 2008
    403
    17
    Tap the tubes lightly one at a time.
    See if you can influence the noise in this way.
    It is most likely the output tube(s).
    It may also be a bad solder connection after the volume control circuit. Any good technician should be able to fix your amp.
    The older he is, the better :)
     
  10. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
    2,039
    287
    I resemble that remark! :)
     
Loading...