Valhalla issue

PKRPedals

Active member
I have noticed a couple quirky things with my Valhalla since building it. It has the same squeal/oscillation that my pineapple has when the gain is up around 2 oclock. Also when turning down the eq section all the way, it kills the volume. I run my cable from the power amp out to the front of the amp, it actually sounds better to me this way, and the pedal acts like a mute when you switch it off, but this my be normal for it to do that. Just thought I would bring it up. I have used all my guitars with this pedal and the pineapple and they all cause the squeal. I thought my Les Paul was different but turns out it does it to. These are the only 2 pedals that I have this issue with and I can't seem to figure it out. I reran my cables in the pineapple with shielded cables and that may have helped a bit, but it still has the squeal. My Thermionic and Thermionic Deluxe don't have the squeal. Now with all that said, these pedals sound amazing but I have to roll off my volume just a bit to make the squeal go away. I can deal with it but would rather it work properly. Any ideas?
 
No, but that's not the point. We're pulling IC1 as a diagnostic to help us narrow down where the problem lies.
I was just making some light hearted Humour. I agree that the traces are further apart on the Original & this being more Compact can cause it to be more prone to Oscillate just like the other versions of this circuit available out there.
If a Klon type buffer fixed the issue then Everybody is happy, Unless they are a ''True Bypass'' Only type!
 
The original is buffered bypass, but the additional buffer could still be inserted into a true-bypass config if desired.

This is one of the older layouts here, it might be time for an update to re-route traces and clean things up a bit...
Interested. Even if it has to go into a larger enclosure, that would be fine. The original is pretty large, and sometimes size matters.
 
I did. I only put the buffer on the one but both circuits do exactly the same thing. If you need me to, I will verify the other is good also. The one that is in my avatar is the one that I play and just stick my Kliche in front of it and it works perfect.
 
I was just making some light hearted Humour. I agree that the traces are further apart on the Original & this being more Compact can cause it to be more prone to Oscillate just like the other versions of this circuit available out there.
If a Klon type buffer fixed the issue then Everybody is happy, Unless they are a ''True Bypass'' Only type!

Ha ha ha ha ha, I totally zoned on that one.
My concern is that if this board is prone to oscillation, the Klon buffer may not be a reliable fix. Could work for some builds and not others, or could work for a while and then one day, at the most inconvenient moment, start oscillating.
 
I’m going to tie it into the input of the finished one tomorrow and see if it works. I feel pretty sure that it will, if only temporary. Maybe Pedalpcb will update this board and spread it out some, maybe that will do it. I'm enjoying being part of research and development. lol
 
I did something pretty cool. I built a switcher and put a buffer in the first loop. That is where the Valhalla will go if it’s on the board. Hooked it up and no squeal. Here are some pics of the switcher. I had some guitarpcb boards so I used them.
 

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When you mention the buffer, is that something at the switch? I see they offer breakout boards for the c bypass, so if a buffer was desired, you'd just use one of those?
 
I also finished the Valhalla a while ago. It sounds amazing, but of course squal after 2 o clock ^^
So what is the most efficient way to make it work with a buffer without building a separate switcher that will go to the input of the Valhalla?

Or has it to be done like you did?

Regards,
Patrick
 
I also finished the Valhalla a while ago. It sounds amazing, but of course squal after 2 o clock ^^
So what is the most efficient way to make it work with a buffer without building a separate switcher that will go to the input of the Valhalla?

Or has it to be done like you did?

Regards,
Patrick
This is all that is needed to be installed if you can build it on Vero
You want the TL072 Layout :

I tried to show it roughly to Scale
Klon Buffer - TL072 - Ivlark.jpg
 
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This is my "Always On" Klone Buffer Eyelet version I designed & built around 5 years ago, Electro's & Caps are on the Underside.
The Enclosure measures 90mm x 35mm ( 3 1/2 '' x 1 3/8 '' )
The 3mm Cap screws hold the FR-4 Eyelet Board in place with a Nylon Hex Riser.
A couple are in Germany somewhere...

Klone Buffer Pedal 1.jpg Klone Buffer Pedal 2.jpg
 
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Valhalla wth Klon Buffer Mock up :
 
I also finished the Valhalla a while ago. It sounds amazing, but of course squal after 2 o clock ^^
So what is the most efficient way to make it work with a buffer without building a separate switcher that will go to the input of the Valhalla?

Or has it to be done like you did?

Regards,
Patrick
The easiest thing to do is put a Boss pedal in front of it. You don't have to turn it on, just have it there. I built a switcher with a buffer built in and it works great. I tried the buffer that Music6000 is suggesting and it works perfect, so that's another way to go also. Don't give up on it though, it's a really good sounding pedal.
 
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