Help! Self-oscillating Bassdrum

  • I have found a wrong resistor: R170 was 470 Ohm instead of 470K.

    Now the strange beeps are gone, but the 50 Hz hum is still there quite loud. I hear a faint click of the kickdrum but the whole thing is very sensitive when I touch earth, like the metal parts of the pot meters! Anybody have a clue?
    I'll try and see if there are more parts wrong. I HAVE TO FIND THE FAULT :twisted: :lol:
  • Hello,

    I think I had the same issue with the hum sound of the bassdrum. As you said it was generally by touching the potentiometer. Have you soldered all the metal parts of the potentiometer that serve as support to the ground? I think I solves the hum by doing that.
  • Hi,
    Thank you for your help!

    I solved the decay problem, it was a wrong resistor after I searched and searched.

    Now it is working fine except for the ground loop hum. I also completed the snare and both the snare and bass drum have quite low volume. I will try and measure where could be a ground loop and also try to measure the signal path why the volume is so low.

    But still I already reaaaaally enjoy the sounds!! :lol: Thank you!