Problem with Chaos Machine

Matmos

New member
Hello! I need your help!
I've just finished to build the Chaos Machine. Everything seems to be in the right place, led is turning on, sound is passing throught when off. But when I turn on the pedal I only have white noise, no guitar sound and no effect.

Ps As you can see in the picture, I've used the alternate wiring with no jacks for expression inputs.
 

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1. Give that board a clean with IPA just to be sure. There may be a short that can easily be fixed.
2. Is your guitar and amp plugged in to the right sockets? Bypass will work if they are in the wrong jacks, but not when engaged.
3. Did you check the volume pot to make sure it's not turned all the way down? I posted something here with that stupid mistake I've done so dont be upset...
4. Is there power to your TL072? Check the voltages
 
1. Give that board a clean with IPA just to be sure. There may be a short that can easily be fixed.
2. Is your guitar and amp plugged in to the right sockets? Bypass will work if they are in the wrong jacks, but not when engaged.
3. Did you check the volume pot to make sure it's not turned all the way down? I posted something here with that stupid mistake I've done so dont be upset...
4. Is there power to your TL072? Check the voltages
1) I'll try that, definetely
2) guitar is plugged into the right sockets, yes
3) pots are all to max
4) TL072 is powered

It's strange, never happened to me before, this whooshing sound when the pedal is on...
Do you think is better to solder the transistors directly to the pcb?
 
1) I'll try that, definetely
2) guitar is plugged into the right sockets, yes
3) pots are all to max
4) TL072 is powered

It's strange, never happened to me before, this whooshing sound when the pedal is on...
Do you think is better to solder the transistors directly to the pcb?
What voltages are you getting on the opamps?

The transistors should be fine in sockets for testing you may want to put a dab of solder on one leg before you box it.
 
Hello! I need your help!
I've just finished to build the Chaos Machine. Everything seems to be in the right place, led is turning on, sound is passing throught when off. But when I turn on the pedal I only have white noise, no guitar sound and no effect.

Ps As you can see in the picture, I've used the alternate wiring with no jacks for expression inputs.
Can you confirm what colour your 5th Band on your resistors are - Brown?
 
Hello! I need your help!
I've just finished to build the Chaos Machine. Everything seems to be in the right place, led is turning on, sound is passing throught when off. But when I turn on the pedal I only have white noise, no guitar sound and no effect.

Ps As you can see in the picture, I've used the alternate wiring with no jacks for expression inputs.
Can you confirm the Input & Output jack external Leads are plugged in the right way?
 
Interested to know if you were able to solve the whooshing. I have it too, but I haven’t boxed up yet and have jumpers on the expression pedal slots for now.
Another super strange thing I just noticed is that the effects work (with whooshing) when the pedal is facing upright (pots on top), but if you turn it over, the effects stop!! More tinkering to be done here.
 
Reviving this, did you ever find the problem? I have the same issue with my build I finished last night - I suspect it may be the isolated expression jacks grounding on the bottom of the enclosure, but I have not had time to troubleshoot. After I do I may post my own thread.
-Alex
 
Hi, I didn’t manage to find the resolution. Others have hinted towards better shielding the wiring as it passes close to some of the components (ICs I think). I noticed that the whooshing was bearable when the pots were not at their extreme settings, so I just boxed it up and avoid extreme settings. Let me know if the grounding analysis reveals anything useful. Cheers.
 
Hi, I didn’t manage to find the resolution. Others have hinted towards better shielding the wiring as it passes close to some of the components (ICs I think). I noticed that the whooshing was bearable when the pots were not at their extreme settings, so I just boxed it up and avoid extreme settings. Let me know if the grounding analysis reveals anything useful. Cheers.
I realized that I didn't drill my expression jack holes large enough and it was grounding through the bolt. After properly mounting the jacks the pedal works (more or less) but there is a wooshing that increases in intensity with the mix knobs of the individual filters and goes at the same rate as the rate knob that makes the pedal pretty annoying to use, also I don't think the "direct" knob is doing anything. I will post my own troubleshooting thread to see if anyone has any ideas.
 
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