1. Register NOW and become part of this fantastic knowledge base forum! This message will go away once you have registered.

Sputtering noise in mics

Discussion in 'Pro Audio Equipment' started by John Stafford, Apr 1, 2005.

  1. John Stafford

    John Stafford Well-Known Member

    Hi all
    I have a tube mic that intermittently makes a sputtering noise. I've had that before on other mics, but it was caused by condensation and easily fixed. I know a faulty tube can cause this as well.

    If the above causes can be ruled out, is there another reason why this should happen?

    John Stafford
  2. Sebatron

    Sebatron Well-Known Member

    It's almost definately moisture in the capsual/element.

    You could try this.....
    Short out the element by bridging a wire across the two terminals of it.
    Listen to the noise of the electronics only.

    If the spluttering is still there that confirms it ain't in the element.

    Re-solder solder joints using fresh solder....
    Clean out the tube/valve socket.
    Maybe replace valve...
    Clean the pins on the valve with emery/sand paper etc. so they are shiney and not looking corroded...
    Examine any electrolytics for leakage....replace if required .... ( though this is unlikely).....

    If the noise disappears when you short out the element ,, then it must be the element....
    In which case i suggest you leaving it outside in the sun between 5 and 10 minutes ........
    Don't cook your gear. :lol:

    Hope this helps.

  3. John Stafford

    John Stafford Well-Known Member

    That's a brilliant idea! This sounds the same as the sputtering caused by moisture, but I've tried everything and the sputtering had gone away, but it just returned and i can't imagine how. Having said all that, this capsule is hyper sensitive to humidity (if I breath near the mic it starts to misbehave).

    I'll try that shorting idea first.

    I really appreciate your help :cool:

  4. John Stafford

    John Stafford Well-Known Member

    The capsule has three wires coming from it. There's one from the centre of each diaphragm, and another from the body of the capsule itself. Should I connect the capsule wires to the one from the capsule body?

    BTW when I remove the grilles the hum is very high, so I hope that won't stop me listening to the electronics.

    I really appreciate your help :D

  5. John Stafford

    John Stafford Well-Known Member

    I've connected the centre of each capsule to the body. All I can hear is valve hiss, with a very mild hum. Actually, there's less hum than when the capsule is working!

    This is very reassuring. I was certain that I had done everything possible to get rid of capsule moisture, but I'll just have to try harder!

    Thanks again :D


Share This Page