Quick switch popping question

[Hiwatt25]

I searched and read several posts about switch popping so I think I have a good idea why it happens and how to remedy it.  What I don't understand is where (physically) the pulldown resistors should be put to help eliminate the popping. 

Does anyone know of a schematic example of how these resistors would look when wired in?  For me I need to see it in order to understand it fully.  I just can't get my head around exactly where they belong. 

Thanks in advance.

[foxfire]

from everything that i have been told and read, it would be put between the switch and the "in" of the circuit with one leg going to ground.

[foxfire]

r1 would be the pulldown resistor in this, http://www.generalguitargadgets.com/diagrams/dist_plus_sc.gif.

[Mark Hammer]

Think of it this way.  There will almost always be an input capacitor between the "input" to the circuit and the first semiconductor (whether transistor or op-amp/chip).  That cap is there to block any DC coming in along with the input signal from reaching those semiconductors.  Any DC that gets stored in that capacitor HAS to have a way to constantly leak out gradually, rather than in a burst.  If the capacitor has one end "free" when you're not using the effect, the stored current will have nowhere to go and won't be able to leak out "off-line".  That path for leaking is provided by the terminating/input resistor.

The resistance/resistor itself can go anywhere that the input capacitor' "free end" is hardwired to.  The cap doesn't really care.  All it wants is a way to bleed to ground.  That path can be provided by a resistor adjacent, a resistor clear over on the other corner/side of the circuit board, OR between ground and the solder lug on the stompswitch where the wire to the circuit-boards signal input goes.  Some circuit layouts provide the convenience of including the terminating resistor on the board, but if it isn't there, a resistor tacked on to the stompswitch (and connected to ground) will work every bit as well.

Generally, you want the largest value resistor you can get away with.  Too small and it loads down the effect.  Too high and it "strangles" the capacitor so that not enough current bleeds to ground in time for the next time you hit the switch.  Between 1m and 2M7 seems to be about right in most instances.

[markm]

Joe,
In reference to the circuit you PM'd me about, put it between the "in" side of R1 and ground.
That should work provided the problem is from DC on the input cap.

[Hiwatt25]

Ah, okay.  Thanks all.  I'm seeing it in my head now.  Makes more sense.   

[adding_to_the_noise]

what do you do if there is a pulldown resistor and there is still a popping noise when switching?

[Mark Hammer]

There should be a pulldown resistor/resistance on input AND output.  Input pulldowns don't solve EVERYTHING.

[Barcode80]

if the pulldown doesn't work and your wiring is solid, check out the LED noise mod on AMZ