SOLVED Switch popping and noise galore with Bootleg and Glory Hole

[KR Sound]

Here’s what I’m building- dual Bootleg and Glory Hole with order switcher.



I tested them both prior to assembly without LEDs in the test platform and they both sounded great.

Now I put them all together and I’m getting switch pops on both and crazy noise from the BL

I took them both out, removed the LEDs and put them in the test platform with the footswitches attached.

BOOTLEG:
Bootleg still popped and buzzed at high gain and volume.

Removing the LED gets rid of the popping, but there’s still high gain buzz. I even swapped out all the ICs just cause.

https://docs.pedalpcb.com/project/BootlegOD.pdf

GLORY HOLE:
Changed the footswitch, changed LED, removed LED, and still have popping. The only thing different from the BOM is an 18k resistor for the LED.

https://docs.pedalpcb.com/project/GloryHole.pdf

There’s not much to this and I’ve built it before without any issues. I’m about to swap out the caps to see and then try the approaches on AMZfx perhaps.

AMZ - LED Popping

How to stop the pops in audio from LED current surges when switched.

www.muzique.com

What am I missing?

 

[KR Sound]

Man, this is driving me crazy, I’ve tried several things, and the LEDs are making it pop. Even on the auditorium when I slowly toggle the switch. I put in new caps as well.

I was hoping to deliver it this weekend, but definitely can’t hand it off like this.

Power supply is a CIOKS7

 

[chris.knudson]

The CIOKs7 isn't your problem. I haven't really studied these circuits too much, but I'm guessing it's a grounding issue. Are all of your grounds tied together?

 

[manfesto]

Might start with the electrolytics in the audio path. The current that electrolytics leak can cause popping and other weirdnesses when they’re in the audio path (and why I usually default to subbing in film or tantalum in the audio path unless there’s a specific and good reason not to).

 

[manfesto]

Also, there’s no reason that C11 needs to be 10u on the Bootleg, you can definitely get away with a 1u Film or Tantalum with no noticeable change. I’m assuming JHS went with 10u there just because that’s what it was on the original TS.

EDIT: probably same with C9 on the Gloryhole.

They’re DC blocking caps, and a 1u cap is a large enough value to allow through all of the audible frequencies a guitar can make.

 

[KR Sound]

Also, there’s no reason that C11 needs to be 10u on the Bootleg, you can definitely get away with a 1u Film or Tantalum with no noticeable change. I’m assuming JHS went with 10u there just because that’s what it was on the original TS.

EDIT: probably same with C9 on the Gloryhole.

They’re DC blocking caps, and a 1u cap is a large enough value to allow through all of the audible frequencies a guitar can make.

No luck with either of those changes. I’m going to have to come back to this later and see if I’m missing something obvious on these.

Appreciate the advice

 

[JTEX]

Is your enclosure and everything metallic that touches it actually grounded, or does the paint prevent grounding around the jacks/pots/switches?

 

[KR Sound]

Is your enclosure and everything metallic that touches it actually grounded, or does the paint prevent grounding around the jacks/pots/switches?

It’s all touching bare metal.

I swapped in @szukalski relay and moved the led to that, and that took care of any popping. I’m just going to go with it for this project and build another to see if I can’t replicate it.

Lucky him, he’s getting momentary switches.

 

[szukalski]

I swapped in @szukalski relay and moved the led to that, and that took care of any popping. I’m just going to go with it for this project and build another to see if I can’t replicate it.

I uploaded v2.1 of the layout today:

GitHub - szukalski/pedal-simple-relay

Contribute to szukalski/pedal-simple-relay development by creating an account on GitHub.

github.com

Same components, smaller layout. More wide and less high, so it fits in better with the footswitch:

 

[KR Sound]

I uploaded v2.1 of the layout today:

GitHub - szukalski/pedal-simple-relay

Contribute to szukalski/pedal-simple-relay development by creating an account on GitHub.

github.com

Same components, smaller layout. More wide and less high, so it fits in better with the footswitch:
View attachment 68917

Awesome. I’ll get those sent off to make a batch.

What do you think it would take to make these either reversible, or to be able to have an LED option on both ends? Or maybe make one that swaps the layout to have the LeD on the other side.

For instances like these:

 

[szukalski]

It’d make the layout larger to swap the LED to the other side. Easily doable but it’ll cost a bit of height.

 

[KR Sound]

It’d make the layout larger to swap the LED to the other side. Easily doable but it’ll cost a bit of height.

I made it work.

 

[KR Sound]

Well, I definitely have something out of whack now with the Bootleg. It’s Microphonic like crazy. I tap on the enclosure and it’s like knocking your pickups with a screwdriver. I’m about to start all over. Or set it aside for a while.

 

[chris.knudson]

I still think it's a grounding issue. You have two pedals operating at different voltages sharing a common ground.

EDIT: I'll be the first to admit that I don't really know what I'm talking about here, but when I look at the two circuits and read the description of the issues you're having, that's where I'd be looking.

 

[KR Sound]

Right? Makes sense. With my DMM, I have continuity between the enclosure, and every ground point on the boards, the relays, and the jacks. I either have something majorly farked or some tiny gremlin. And I’ve been on such a streak with no issues this past year Guess I’m due.

 

[chris.knudson]

I'm thinking you have a ground loop. I don't know if there's a way to isolate the grounds or connect a ground lift to one side of the circuit. If you google ground loops and look at the Wikipedia page. There are several different ways listed to correct ground loops. Don't know -- might be helpful.

EDIT: and the more I think about it, that could have also been the source of the LED pop you were getting. I'm not sure how those footswitch PCBs are wired, but if those are true bypass, then every time you engaged the footswitch, you were creating a voltage differential across ground, which would result in a pop. It's just a theory, but it sort of makes sense to me.

 

[eh là bas ma]

I had a loud popping noise issue on a circuit once, i couldn't find a way to fix it, even with AMZ tricks, and 20k led resistor.

Finally, i've been suggested to add a 10n DC blocking cap at the beginning of the circuit and it fixed it.

TL72IP or TL72CP question, and popping apostle.

TL72IP or TL72CP question, and popping apostle.

www.diystompboxes.com

Edit : that's what i did on the apostle circuit :


Not sure if this will be helpful in your current application, but maybe it could.

 

[KR Sound]

Moving both grounds from the jacks to the center creating a star ground helps immensely. Each one is pretty quiet with no microphonics when on by themselves. When they’re both on all hell breaks loose. The order switcher is the only thing I’ve never used before.

Quick crappy solder job:

 

[chris.knudson]

Hmmm, can you tap the ground off of the switch to the center lug as well?

EDIT: Ok, so now I'm fairly convinced that the issue is a ground loop. With both pedals on, you are basically creating a voltage differential between the two circuits. What you need is a way to equalize the reference voltage of what both pedals see as ground. It's easy to think of ground as 0V, but the problem is that only works when the reference voltage is common. In this case, you have two different reference voltages, and and I'm guessing that is creating a differential at the grounding point and causing "all hell to break loose" when both pedals are powered on. If it's DC voltage, a capacitor connected to the ground lead could solve the problem, but in this case it's its AC voltage, which presents a different challenge. Unfortunately, this is already way over my head. I mean I think I understand the problem, but I don't know how to fix it.

 

[KR Sound]

There isn’t one- it’s a conduit between the INs and OUTs of the two pedals and the jacks.

3PDT Order Switch Wiring - PedalPCB Wiki

wiki.pedalpcb.com

Unless I hook something up to the case of the switch.

I’ll have to try it in the morning, everyone’s gone to bed for the night.