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very nice!

Now I need a picture of the fix, otherwise it will haunt me in my dreams every time I buy online.

Resistor sounds right.
Is the noise only on one side of C6?
Could it be the capacitor?
I though the green caps are kind of inductive, and try to avoid using them, but it could be just misinformation...

Omg, just came by to praise the wiring.
The plexi lid is a must with such an organized interior

Nice, I also like my builds in layers.
The 3D printed part is a nice touch
Using the lid also helps to get a better view, have to try that one at least once.

Do you think it changes with the speed knob, and could be associated with the LFO?
Or is it more like delay feedback oscillation?

The first case would be leaking LFO. But that would be weird, since it should be there when you remove the BBD.

The second case would be a short somewhere in the wet line to the input or a specific position of the input.
What is weird, is that it should be really fast. Maybe the LFO changes that.

My next suggestion would be AC grounding some places through a cap (anything between 100n to 100 uF, one leg to the signal path, the other to ground). Start from the mixer stage and go towards the BBD. It will short the wet signal and at some point there should be no noise left.

If you are lucky, it is in the region where the signal is shorted to the input. Otherwise, you just cut to much of the signal.

Ok, that changes things a bit.

Distortion can be a result of wrong bias somewhere. Probably at the input of the BBD.

My suggestion would be analysing parts of the circuit:
First, remove the mix resistors (If the MN3207 is socketed removing it will break the signal chain there, and no desoldering is necessary).

Let's hear how it sounds without chorus at all (just the clean sound). If there is something wrong with an OpAmp it should be noticiable.

Second, there should be no distortion (when using the audio probe) until you get to the input of the BBD. Chorus do not have feedback, so there should be nothing returning to the begining of the signal chain.

Third would be to remove everything associated with the BBD (clock, BBD, LFO(TL062)) and see if the clean signal works now.

That should give an idea where the Problem is.

Well, that might be a cold solder joint at some ground in the circuit. Every time I have buzz it's either a bad cable or wiring problem.
Your wiring looks exactly like the one in the PDF, but It could present some lose or cold joints.

How are you using the audio probe? Are grounds connected? There should be no noise at R1.
Noise at R1 means noise at the input jack. Any weird noise caused by the circuit should not be present at the input, unless there is a problem with grounding.

Does it work when bypassed? Or is the noise bleeding through even when bypassed?
Can you check continuity between some ground points and some components? For example, one side of R1 should be grounded.

Which build doc are you using? I have the 2019 one, and voltages seem correct for the MN3007.
Voltages on IC2 depend on the type of BBD that you used, though.
Unfortunately, the image is too dark to identify your IC2. Voltages suggest a **3207. Are you using the correct clock (3102)?

Have you tried checking the signal path with an audio probe?

That looks gorgeous!

That looks nice, is that the primer or some sort of hammer paint?

What about jumping r38?
Depth only goes to 90% with it in place.

The second OpAmp max. gain (above the 100n bypass) should be
-R_feedback/R_input=(220k+1M||470k)/220k=-2.45.
If you remove the 470k resistor it goes up to 5.45.

Nice set!

those smd parts give me nightmares, good to know they have this kind of service.

Nice,
really liked the shape knob.
Now I have to check what it does.

Hi,
to understand how it works:
- VCO receives a fixed voltage and outputs a fixed frequency
- As a result the BBD outputs a fixed delay (no flanging)
- The metallic sound has to do with the very fast delay and how it combines with the original signal (basically the flanging is stuck at a position)

So, first thing you can check, if you have an audio probe, is whether there is signal at the output of the BBD. If there is no signal, there is something wrong.

You can then check if the clock pins of the BBD have any clock signal. If there is no voltage at those pins or it is too low there is something wrong with the VCO.

By checking the input of the VCO (pin 3) you can verify which voltage it receives in matrix mode. If this voltage is below a certain value the effect will not work. I played with the VCO in mine by connecting the input directly to a pot connected between ground and 9V and I could adjust the voltage at the input and get different clock frequencies. The matrix mode can sound different depending on the voltage setting.

In the original this is provided by the OpAmp, so if the voltage at the VCO is wrong it might be something with the OpAmp, which inputs are controlled by the matrix switch. So, that is why I suggest looking at the switch first. If the OpAmp is biased wrong there will be a wrong voltage at the VCO, resulting in a wrong clock frequency, and no apparent effect.