not having any luck de-popping my pedal.

Started by foxfire, June 26, 2007, 06:54:10 PM

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foxfire

my fuzz jade/buff-n-blender build is popping. i disconnected the led and it still popped so i tried a 470k, 1m, 4.7m resistors in the input of the blender without any improvement. i tried the same 3 resistors on the input of the fuzz jade also without any improvement. any suggestions for me? i searched but didn't see anything like my situation.

jlullo

rylan,
do you mean you tried those pulldown resistors at the input caps of each pedal?

try pulldown resistors on your in and output caps of both.

this is a very good article to read on this situation:
http://geofex.com/Article_Folders/box_pop.htm

also, check your connections on your switch.  I had a popping problem that was caused by crappy soldering somewhere on my 3pdt switch

foxfire

do you mean you tried those pulldown resistors at the input caps of each pedal?

yup, i put the pulldown resistors right in front of the input caps.
should i be focusing on the blender since the fuzz goes in and out of it or should i focus on the fuzz cause it has way more gain? and thanks for the link.

foxfire

ok so i have a 1m on the blenders input to ground and a 4.7m to ground on both the input and output of the fuzz. still pops.

R.G.

Pulldowns only eliminate pops when input/output capacitor leakage is the problem. If you accidentally get capacitors backwards, they leak so much the pulldowns can't keep up. Likewise, if you have a short or a wiring problem that puts DC outside the capacitors, then rubbing on an ointment made from pulldown resistors does not help.

Use you DMM and look for DC on the inputs and outputs of your effect where the input and output caps should be blocking it.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

foxfire

Quote from: R.G. on June 26, 2007, 08:05:33 PM
Pulldowns only eliminate pops when input/output capacitor leakage is the problem. If you accidentally get capacitors backwards, they leak so much the pulldowns can't keep up. Likewise, if you have a short or a wiring problem that puts DC outside the capacitors, then rubbing on an ointment made from pulldown resistors does not help.

Use you DMM and look for DC on the inputs and outputs of your effect where the input and output caps should be blocking it.

firstly thank you for the suggestion. with a cable in the input jack and the pedal on standby i get 0mv.

ulysses

have you tried grounded input or grounded output switching?

cheers
ulysses

foxfire

this is how i wired it. i got this diagram from the byoc forum. i searched 10 pages deep for the post i got it from so i could give credit to it's maker with no luck. i absolutely take it down if asked to. thank for the diagram and sorry if i have made a mistake by posting it.


ulysses

try it with grounded output instead

refer to http://aronnelson.com/gallery/ulysses_wiring_diagrams/ulysses_grounded_input_veri

make the following changes - swap board in with board out and swap input jack with output jack

cheers
ulysses

foxfire

i'll have to try that when i get home. thank you Ulysses.

foxfire


Gus

An important bit of information is missing, what switch brand?

Some switches can be damaged by to much heat when soldering.


foxfire

it's a blue E-H. and i do have to say that this was/is my cleanest switch yet as far as my soldering work. i decided not to rush getting this pedal done cause i had a feeling i was going to love it. with that said i'll try another switch tomorrow.

foxfire

ok so i reread the geo link jlullo posted and tested my pedal. with it in bypass i get 0dcv on both i and outputs. with it on i get 0dcv on the input and anywhere from 0dcv to .6mv on the output. thats with a 100k pulldown resistor on the output cap of the fuzz jade. i'm not sure what to do with info though? i know it means that i have dc voltage where i shouldn't, but i'm not sure what i should be looking at to fix it?

ulysses

i was going to suggest that you post a sound clip of the pop after playing so i can hear how loud it is.

with some 3pdt there is always going to be some sort of click introduced by the physical plate clicking in the switch.

but if you have dc voltage on the output then you have a problem.

ask others if they have built the same circuit to test whether they have dc on the output.

have you made mods to the circuit?

try sticking an output cap on the output of the circuit to block the dc.

cheers
ulysses

foxfire

the only mod i did was to change the tone stack values a bit. i tried adding a few different valued output caps to the output, still pops. i'll put up a post on the common sound forum and see if i get any hits. tell you what if i ever meet a leprechaun i know what one of my wishes will be. thanks again for the help.

foxfire

how do you get rid of dc? i have tried swapping in new caps in place of the old output caps and i still get dc in my output signal? i posted over on the common sound forum and i got the same response that you all have said. i.e. there shouldn't be any dc.  i have tried 4 different caps in the fuzz's output and at least 1 or 2 in the blender. are all my caps leaky? and if they are is there another way to keep the dc from getting into the output signal?

plankspank

Double check all your ground connections from the schematic- if you have any floating grounds, you would get " popping.....good luck