Valhalla Distortion issues

[ammendes]

Hello, I'm new to the forum.
Built a couple of pedals before (a delay, a noise gate and a compressor. No issues there).
My knowledge on circuitry is not the best compared to the craziness I read around this forum, so bear with me.

I built a Valhalla Distortion and I'm getting the famous squeaking.

I went through every component, and found that all of them are correct and correctly placed on the board.

When using the POWER OUT, with the pedal off there is no sound, as expected. When I turn it on I get a big squeak that can be played around using the EQ and Gain knobs on the pedal. I can make the squeal go away by lowering everything. I can hear my guitar with distortion, but very muddy and far away.

When using the normal output, the bypass sound is perfect, no buzzes. When I turn the pedal on it goes into squeak and hum mode.

Funny fact, when I have it on, just touching the pots on the pedal or the ones on my guitar, and also touching the strings, changes the frequency of the noise. Also, when I throw a chord on the guitar, the squeak kind of goes away. It squeaks when the guitar is idle most of all.

I've read around threads, and saw a fix involving adding a buffer pedal before the valhalla. I don't have a boss pedal. Tried adding in a noise gate I got from Musikding, that pretty much clears the sound totally. Also saw people introducing a second board on the pedal itself, but the reason for that goes beyond my knowledge.

Can I get some help here please? How should I go about troubleshooting this?

Thanks!

Here's some pics of what I have. I use a 3d printed enclosure, and I removed everything from there except the DC input to take the pics. Happy to take more pictures of any detail you wish

 

[falkry05]

I built the aionfx version and it squeals without a buffer pedal before it, or something like an OD.

 

[Nostradoomus]

The second board addition is more than likely a buffer to help tame the squeal. They only use a handful of parts and can be made quite easily on stripboard etc. Boss pedals aren't the only ones with buffers, just the most common.

 

[music6000]

1. Confirm, you have rubber pads under the 3 pots in the middle of the PCB?
2. I looks like you have Yellow & Black wires going to ground on your jacks?????

 

[Chuck D. Bones]

That enclosure is non-conductive, right? You need to find a way to connect all of the pot bodies to GND. One option is to get Cu or Al tape and cover the inside with a conductive layer. Next best option is to solder a ground wire to every pot body and connect that to one of the board grounds. This is a very high-gain pedal and we need to get the grounding and shielding right.

Your soldering looks pretty good. A couple of solder joints look iffy in the pix. They might be ok, but check them under magnification and touch-up anything that's questionable. I am NOT suggesting that you reflow every solder joint.

I assume that the three pots under the board also have insulating buttons on them. for future reference, the pots that hang off of the board do not need the buttons.

I don't trust those stamped metal pin sockets. The have a reputation for making poor contact. They're probably ok, but if you must use sockets, spend the extra $$$ for machined pin sockets.

The wires from the stomp switch to the board are too long and will act as antennae. Make them as short as possible.

Does the pitch of the squeal change if you rotate any of the knobs?

The second board addition is more than likely a buffer to help tame the squeal. They only use a handful of parts and can be made quite easily on stripboard etc. Boss pedals aren't the only ones with buffers, just the most common.

That's a band-aid. If the unit is built right, then the buffer is not necessary.

 

[ammendes]

The second board addition is more than likely a buffer to help tame the squeal. They only use a handful of parts and can be made quite easily on stripboard etc. Boss pedals aren't the only ones with buffers, just the most common.

1. Confirm, you have rubber pads under the 3 pots in the middle of the PCB?
2. I looks like you have Yellow & Black going to ground on your jacks?????

1. All pots have rubber pads
2. All jacks are wired with ground (black) on the outside pin, and yellow (live) on the inner pin.

 

[Chuck D. Bones]

1. Confirm, you have rubber pads under the 3 pots in the middle of the PCB?
2. I looks like you have Yellow & Black wires going to ground on your jacks?????

Good catch!

 

[Nostradoomus]

That's a band-aid. If the unit is built right, then the buffer is not necessary.

Oh absolutely, was just speaking to that end haha

 

[Chuck D. Bones]

2. All jacks are wired with ground (black) on the outside pin, and yellow (live) on the inner pin.

Sure looks like yellow wire goes to the sleeve in the pix. Maybe you can show us a close-up of one of the jacks.

 

[ammendes]

That enclosure is non-conductive, right? You need to find a way to connect all of the pot bodies to GND. One option is to get Cu or Al tape and cover the inside with a conductive layer. Next best option is to solder a ground wire to every pot body and connect that to one of the board grounds. This is a very high-gain pedal and we need to get the grounding and shielding right.

Your soldering looks pretty good. A couple of solder joints look iffy in the pix. They might be ok, but check them under magnification and touch-up anything that's questionable. I am NOT suggesting that you reflow every solder joint.

I assume that the three pots under the board also have insulating buttons on them. for future reference, the pots that hang off of the board do not need the buttons.

I don't trust those stamped metal pin sockets. The have a reputation for making poor contact. They're probably ok, but if you must use sockets, spend the extra $$$ for machined pin sockets.

The wires from the stomp switch to the board are too long and will act as antennae. Make them as short as possible.

Does the pitch of the squeal change if you rotate any of the knobs?


That's a band-aid. If the unit is built right, then the buffer is not necessary.

1. Enclosure is non-conductive, it's made of PLA plastic. The sounds this thing is making brings the words "bad grounding" all over my head just intuitively. I never had grounding issues with these enclosures in other pedals, but none of those are distortion pedals. I will follow your advice, I think the wire solution might sound worse but would actually be more robust here =)

2. When I looked again at these pics I noticed the solder joints that look bad. I'm not a professional but I think it's the lighting that makes it look much worse. I reflowed the ones I suspected could be bad before posting here.

3. All pots are covered with rubber pads.

4. By stamped pin sockets, are you refering to the jack in and outs?

5. Will cut the antenas short!

6. The pitch of the squeal changes when I mess with the Treble knob mostly. The Gain knob is almost all or nothing.

 

[ammendes]

Sure looks like yellow wire goes to the sleeve in the pix. Maybe you can show us a close-up of one of the jacks.

I can't believe my eyes.... The wiring on the jacks is reversed....... I'm sorry y'all.
Let me change that and I'll get back to you (tomorrow, I'm in portugal, it's 5 am here, my wife will kill me if she ears another squeal)

 

[ammendes]

I'm just posting this here so you can mock me. I know how to do this and I did it wrong. I should rest.

The jack wiring is reversed in all 3.

Would this cause the squeal though?

 

[Chuck D. Bones]

I meant the IC sockets.

Those jacks are definitely wired backwards.

 

[ammendes]

I meant the IC sockets.

Those jacks are definitely wired backwards.

They came with a kit I bought. I also don't like them, the IC feels like it can jump off of it, and the IC's legs easily go out of contact.

Yep, the jacks are screwed. Thanks for catching that. I'll make the change and report back to y'all

 

[Chuck D. Bones]

Where did you buy your kit? Musikding?

 

[ammendes]

Where did you buy your kit? Musikding?

Yes. Do you mind if I ask why?

 

[music6000]

Hello, I'm new to the forum.
Built a couple of pedals before (a delay, a noise gate and a compressor. No issues there).
My knowledge on circuitry is not the best compared to the craziness I read around this forum, so bear with me.

I built a Valhalla Distortion and I'm getting the famous squeaking.

That was Version1, PedalPCB released V2 & it shouldn't have an issue in a metal enclosure.

 

[ammendes]

I didn't know there were two versions. Now I'm wondering which version I have

 

[music6000]

I didn't know there were two versions. Now I'm wondering which version I have

It was like nearly 5 years ago & all first batch PCB's were replaced then.
Here is a recent Build!:

Valhalla Distortion

I'm kind of at the point where I've mostly built all circuits I set out to build when I initially started. So, now I'm building what I consider "classics". In my opinion, The Diezel VH4 amp is one of those. I've never played one but I've heard plenty. One of the first pedal mods I've ever...

forum.pedalpcb.com

 

[Chuck D. Bones]

Yes. Do you mind if I ask why?

The quality of the parts. Disk ceramic caps. Stamped metal pin IC sockets. An out of date circuit board. 1/4W resistors where 1/8W would be a better fit. I don't buy from Musikding, but I have read many stories in this troubleshooting forum from people who have. It is not uncommon for the parts kit to be incorrect or incomplete. Those are not high-quality jacks. Look at how a 1/4" plug engages in the jack and tell us if it fits properly. Lower quality jacks have the wrong shape or dimensions and the plug does not snap in completely. I bought some jacks at the local electronics store and I had to insert a plug into every one to see if the engagement was good. I rejected about 20% of the ones I checked. They look a lot like yours.