popping

[LightSoundGeometry]

I cant tame the pop on some pedals like the crunch box or the lm386 power amp even with pull down resistors and the amz/jack orman rc bleeder circuits.

the article says some high pedals are just microphonic and pick up the mechanical switch no matter what. although, it didnt pop until boxed up on bypass with led, not on bread board test rig.

live with it, or scrap the circuit ?  it sounds freaking great though !

bad soldering?
bad cap?
its doing without only guitar and amp , so no other pedal.

[Groovenut]

Without knowing the circuit, it's hard to say but...

You might try input and output signal current limiting resistors and see if it helps. Place a 1k at the input and output of the circuit in series with the effect circuit, between the switch and the input and output of the effect.

However, my guess is the input is a high enough impedance and the the gain of the circuit it high enough that it's picking up the mechanical thump of the switch being transmitted through the enclosure and amplifying it through the circuit. I which case, your only hope is to get a switch with a softer click action.

My 2 cents

[Rixen]

there's a long discussion on this subject on this thread:

http://www.diystompboxes.com/smfforum/index.php?topic=114186.0

switching pops and clicks can be very hard to get rid of. Even in a passive circuit.

[LightSoundGeometry]

hey thanks guys. i appreciate the feedback . I either use BLMS or small bear. the last batch of switches, the ones these are from, are from blms

im using GFX vero layout ..the pedal kicks ass just that pop it gives off ..its not all that bad when playing but its really loud when not strumming.

http://tagboardeffects.blogspot.com/2012/02/mi-audio-crunch-box-v2.html

I think will give the signal limiting mod a shot and get back to you on that!  my soldering looks fine and the caps are good ..

I just noticed in comment section, missed it earlier, marks says to take another 1m from input jack/board input to led ground lead ..I have never tried that , just have tied one right to common but is that not still common ? or is it dumping right out of the led before it hits the switch ?

i have LED neg lead to lug 4 and then lug 5 to ground through a 2k2 limit ,so what mark is suggesting in gfx comments has that 1m dumping before led hits bypass...going to try both ways here n about 1-2 hours ..eyes are killing me!

[amptramp]

Try disconnecting the LED and see if you still have the same problem.  In some cases, the LED draws enough current to change the voltage in the circuit by moving the ground and Vcc voltages.

3PDT switches also have a problem in that there is a race between switch poles.  If the ground to the input of the effect is disconnected then the LED is switched, you have an open input seeing a voltage shift and this gets amplified.  If the LED is switched first, you won't hear much.  The difference in switching times is in milliseconds and guess what - that puts it in the audio band.

Diode switching and CD4007 switching allow some control of the rate of switching but that requires more parts.

[LightSoundGeometry]

Try disconnecting the LED and see if you still have the same problem.  In some cases, the LED draws enough current to change the voltage in the circuit by moving the ground and Vcc voltages.

3PDT switches also have a problem in that there is a race between switch poles.  If the ground to the input of the effect is disconnected then the LED is switched, you have an open input seeing a voltage shift and this gets amplified.  If the LED is switched first, you won't hear much.  The difference in switching times is in milliseconds and guess what - that puts it in the audio band.

Diode switching and CD4007 switching allow some control of the rate of switching but that requires more parts.

still a pop but its not too bad when the amp is up, only loud when I am not strumming and click it now. so what makes this pedal sounds so good? my goodness it is a beast ..wow.

I have a 1m pulldown at input, a 4m7 on output, a 4m7 on lug 2 out to ground, jack ormans delay now with a 100uF, an extra power filter cap and mark from gfx 1m from led lead to ground..and the by pass tied to ground

could be my soldering possibly..I think its good enough to live with..my rangemaster pops a little as well..might be my soldering lol!


* i haven't tried GN 1k series yet and I will unhook the led and test as well

supposed to be fixing pop but pedal sounds so good I been jamming for 20- 30 mins at a time ..it sounds like there is some type of wet vibeyness coming out of this thing 


popped with LED unhooked, did not pop in testing when on BB and my rig switch ..back to testing

[LightSoundGeometry]

its the bypass mechanical switch being amplified. I had two of my friends test it on their rigs and the feedback response was same as mine, holy &^%$ ..the popping really cant be heard when your playing and I believe is the nature of the beast. One i told about and the other I didnt to see if he would notice a popping and he didnt even mention it 

Like groovenut suggested, you could use an ultra smooth 3pdt. I am using the standard blood red ones from blms which seem exactly like the ones from tayda. Small bears black alpha are loud just like the others and I found the gold legged upgraded ones from mammoth the smoothest and quietest of the four samples I had on hand. my two test subjects both got a blms switch.

I stuck the red led clipping diodes on the outside of the box lol 

[JerS]

I used to have this issue from time to time when building on vero and could never figure out the reason. Once I settled on a "convention" for grounding, where I ground the board only at the input jack and DC jack, this phenomenon went away. Luck? Quite possibly. YMMV!

[amptramp]

If you want an exercise (in futility?), swap sets of switch poles.  There will always be a race condition where the loudness of the switch pop depends on which pole switches to the opposite side first.  You may find this clears things up or makes things worse.