Crybaby without buffer and with TBPs pops. Pull Down Resistor?

[richon]

Hi,

i put out the Crybaby buffer....  sounded a lot more VINTAGE now... excelent

(but , it is TBPS modded) and , as i put out the buffer (and his pull down resistor) , it's popping again.


should i put a PullDown Resistor before the 68K (input resistor) or after  the 68K (and before the 0.01uf Cap)

[petemoore]

  I don't follow.
  The DC blocking caps [input / output] when switched may release a stored charge.
  By putting a small 'release valve' [large value resistor], the charge can be drained.
  Most modern or modernized schematics show the pulldown resistor position at the outside of the circuits DC blocking capacitor which connects to the BP Switch.
  *=pulldown
  Signal input jack tip, wire,  Switch/*input cap.
  Circuit output>DC blocking output cap* switch > output jack
  A pulldown keeps the floating end of the cap [it'd otherwise be floating when in bypass mode] discharged so when the switch makes contact there is no surge of current to produce a popping sound.

[richon]

Yes PETE,

but let me remind you, in the Wahs its like this:

Input jack - DPDT switch - 68K resistor - 0.01uF Cap - Transistor (and no pull down resistor)... so, should i put the Pulldown resistor before the 68K resistor o between the 68K and the 0.01cap?

[cheeb]

I'd put it between the series resistor and the input cap, if it were me..

[John Lyons]

To function as a pulldown resistor the resistor should be on the outside of the input (or output) cap.
This way any DC voltage from the cap will go to ground through the pulldown resistor.
The resistors is the first thing the switch ior input sees.

john

[petemoore]

  Switch opens a valve, if you have a bunch of stored energy, and that line is in signal path you get 'pop'.
  Put a large value resistor so a little bit of current could flow to ground, at the switch where a capacitor connects.
  There might be some other stuff around there, but caps store charge, switches switch, when a stored charge hits the signal path it goes 'pop' in the amp/speaker.
  Anyway, regardless of the other nearby stuff , there's a DC blocking capacitor, and a switch in the signal path that makes/breaks connections, that's where you want the pulldown located.

[richon]

  Switch opens a valve, if you have a bunch of stored energy, and that line is in signal path you get 'pop'.
  Put a large value resistor so a little bit of current could flow to ground, at the switch where a capacitor connects.
  There might be some other stuff around there, but caps store charge, switches switch, when a stored charge hits the signal path it goes 'pop' in the amp/speaker.
  Anyway, regardless of the other nearby stuff , there's a DC blocking capacitor, and a switch in the signal path that makes/breaks connections, that's where you want the pulldown located.

well finally i did this:

put the 0.01uf cap before the 68K resistor and a 2.2M resistor before the cap (connected to ground) and same sound and no POP. So everyone's happy