What's wrong when ALL my pedals pop?

[R.G.]

so there's a correlation between brightness of LED and popping?

There is a correlation between LED *current* being switched and popping if you do your ground and power supply wiring incorrectly.

But let's get back to cases:

There are good clues here.  Gus asked the big question before I could.  Did you run all these tests with the same guitar?  I suggest you repeat with a different one.  Also, the battery test is another biggie.

Have you tried eliminating
- the guitar?
- the cables?
- the amp?
- the tubes?
and so on instead of chasing LED current? 

[YouAre]

so there's a correlation between brightness of LED and popping?

There is a correlation between LED *current* being switched and popping if you do your ground and power supply wiring incorrectly.

But let's get back to cases:

There are good clues here.  Gus asked the big question before I could.  Did you run all these tests with the same guitar?  I suggest you repeat with a different one.  Also, the battery test is another biggie.

Have you tried eliminating
- the guitar?
- the cables?
- the amp?
- the tubes?
and so on instead of chasing LED current? 

i have been eliminating all day. Like i said, the buffered pedals lose their click once i just cycle the stomp enough. But the DIY true bypass pedals still pop pretty badly. so i'm trying feverishly to eliminate it.

Guitar, pops with both instruments
Cables, swapped them, still pops,
Amp, switched from tube to crate powerblock, still pops

I tried both styles of wiring that i mentioned before, WITHOUT the led, and i'm still getting a pop when the pedal is turned on, but NOT when bypassed. So i'm taking two 1m resistors, on the outboard sides of the input cap (.022 on the screamer) and output (10uf), as per the article of some kooky old effects weird guy. Here's the article http://geofex.com/Article_Folders/box_pop.htm

I'm seriously thinking about going buffer. Anyone know of any bypass buffers? I'm thinking of going the cornish way!

[Toney]

Go Millenium!
Won't pop then.

Have you tried using hi-brites run at a low current?

[Toney]

Just read the thread properly..

You must have DC sneaking in somewhere.
When you say even your 'buffered pedals' pop, do you mean commerical ones Boss etc?

Start with a known-to-be-good Amp/cable/guitar chain before anything else.

[YouAre]

i tried going milenium, and i played around with putting 1M resistors on each lead of the input/output caps. I tried them in all different positions, and i still get a damn pop on my overdrive!

Can anyone tell me how to poke around to find the DC leak?

[slacker]

To see if you've got any DC leakage, poke around the pins of the stomp switch, if you've got DC on any of the pins apart from the one to the LED then you've either:-
got input or output caps that are too leaky
wired something up wrong so DC is getting where it shouldn't
got a dodgy switch

Do the measuring with just a lead plugged into the input jack to turn the pedal on (if you've wired it like that) and measure the voltage in both positions of the stomp and whilst switching it. If you don't get any DC where you shouldn't plug the pedal into your amp and do it again, if you get DC now it means it's your amp input that's got DC on it.

[YouAre]

ok so i did some comparing!

i went out and bought a BBE screamer. Tried it out on my rig, and....pop! So then i tried out my pedal on an amp in a store, jcm800, and it popped at higher gain settings.


So i poked around in my pedal (returned the BBE by now), and just to make sure i'm doing this right, i clipped the black lead of the DMM to the ground lug of the power supply jack, and i poked around with the red. I'm using the regular bypass without LED, and no input grounding. The lug with the input and output of the circuit jumped up to 4mv then slowly died down to 0...odd?

Even more odd, The bypass on the switch (2 lugs jumpered together) went NUTS, jumping up to like 300-400mv. I don't get it.


Would putting big caps as "pulldown caps" help any?

[R.G.]

An overdrive has a large gain. When you put a sudden change on its input, the change is amplified through it to a big pop on the output.

You found a 4mV change which died out. That means that a cap was charged to 4mv different from where it should be, and then charged up/down. Find out where the 4mV is coming from: leaky cap? flux/dust/dirt/corrosion on the board?/ incautiously placed pulldown resistor?

And no, "pulldown caps" won't help, they'll make it worse.

[YouAre]

are there any buffers i could build that would pad down the input/output voltages?

cause I could simply tack those onto any other pedals that have a pop on them. I'd be giving up true bypass, but i don't mind.

also, where should the pulldown resistors be placed ideally?

[R.G.]

OK, we're way out in left field here. Out in the weeds actually.

Can you list exactly the equipment that you're having problems with, from guitar through amp? All the parts, including cords and power supplies.

There are only a few possibilities. One is that you have a bad box in there putting out DC. Another is that you are one of those individuals that for better or worse is more sensitive to pops than the rest of us. There are others. The chances of you building yet another box to glom onto this chain of popping boxes that will fix it all is vanishingly small. Find the problem first, then discuss fixes.

So give us a list of what you have and I (and probably others as well) will try to lead you down the path to finding the problem.

[YouAre]

First off, thanks to all of you who've been helping me out through this.

I would say i am pretty sensitive to the pops because i plan on selling a couple pedals. They're gonna be one off's to some people i know, but i try to keep high standards.


Here's the signal flow.

Gibson LP with Anderson HB's >> Cheap GC cables (or George L's) >> ts808 clone on BYOC board with 1meg pulldowns on input and output of circuit, powered by godlyke 9v power supply >> Another Cheap cable >> fender prosonic head into attenuator or crate powerblock or marshall jcm800 (in the store)

is there anyone to test if there's DC on my amp's input?

[slacker]

is there anyone to test if there's DC on my amp's input?

Yeah, with your DMM set to measure DC plug a guitar lead into the amp then clip the black lead of the DMM to the sleeve of the plug and clip the red lead to the tip. If you measure any DC then it's coming form the amp.

[YouAre]

is there anyone to test if there's DC on my amp's input?

Yeah, with your DMM set to measure DC plug a guitar lead into the amp then clip the black lead of the DMM to the sleeve of the plug and clip the red lead to the tip. If you measure any DC then it's coming form the amp.

when amp is on standby, there's -.495 mv. When its on, about +1.6mv

that contributes to the pop doesn't it....

[YouAre]

bump