Help : Black Eye

[Guipouette]

Hello to everyonne !

I just finished to build my first one, but the pedal don's works !

Do you have an idea what could be the issue(s) ?

When the pedal is off, the bypass is ok. The sound from the guitar to the amp work. But when the pedal is on, no sound (or just a few noise) and the DEL is on.

Already thanks for the help !

Florian

 

[andrewsrea]

Are you getting indicator lights?
I recommend starting with checking the B+ power to the tubes. What is the recommended power supply for that pedal? I assume it would need to be capable of high current switching supply to go from low voltage to 250VDC while also supplying the tube filaments (300ma at 12VDC for two 12AX7 type tubes).

 

[Audandash]

Your footswitch board is upside down. The writing should be on the top so you can read c2c. Not saying it’s the only problem but it is a problem. You will likely need to order a new board as getting a footswitch off without damaging it can be a challenge.

 

[eh là bas ma]

Your footswitch board is upside down. The writing should be on the top so you can read c2c. Not saying it’s the only problem but it is a problem. You will likely need to order a new board as getting a footswitch off without damaging it can be a challenge.

it looks like it's upside down but i dont think it is.

Check this other build reports :

J

Thread 'C2CE Black Eye'

Sep 11, 2025

Another one that’s been in the backlog for a while. I finally got my 9-pin tube sockets in the mail today, so I finished it right after work.

The build is pretty straightforward. The docs for c2ce projects are top notch, and the provided tayda drill and UV templates make the projects even better. I used the tayda drill service for this one.

This thing had so much gain. It’s rad- I love it. I’m thinking of putting it on my board despite the current requirements.

If you think you might like this, you should build it.

• jcpst
• Replies: 8
• Forum: Build Reports

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The usual suspects on this build are the tube-daughterboards connectors, with small soldering pads very close to each other.

 

[eh là bas ma]

Are you getting indicator lights?
I recommend starting with checking the B+ power to the tubes. What is the recommended power supply for that pedal? I assume it would need to be capable of high current switching supply to go from low voltage to 250VDC while also supplying the tube filaments (300ma at 12VDC for two 12AX7 type tubes).

we need 9V+ with at least 500mA to make it work.
There's a voltage pump implemented in the circuit, to make it feed the tubes around 200V from a standard 9V DC power supply.

Good point, that could easily be the issue.

 

[Guipouette]

Thank's for the answer ! I have to find a better power. Today I have only 9v -1A but the voltage isn't very good.
My second alim has a real 9v (but 300ma), but the DEL is already better
When I got one , I tell you

It could be the solution

 

[Audandash]

Power is important with these pedals. I recommend a 1 spot. I would still check the footswitch board. I have never built a c2c board that didn’t have it labeled on top. (Just my experience). It usually says c2c and has a board label like TB or BO. Maybe there are some that don’t. He also usually runs the traces for the footswitch on the bottom. It’s worth taking it out of the box for a quick visual inspection.

 

[Guipouette]

I just tried quicly with my actual power 9V-300mA and it's working. So I'm going to buy a new one and I tell you !!!!

Thanks you very much to every one

 

[eh là bas ma]

I would still check the footswitch board.

If there's a doubt on the 3PDT connections, it's possible to figure it out and hand-wire some new 3PDT.

It's going to be jack IN, PCB IN, GND, V+, PCB OUT, jack OUT, not necessarily in that order.

With a multimeter on continuity test we can see which one is GND, and figure out the rest with a few attempts.

The best would be to add an extra relay bypass, to make the switching process almost completely silent.
There is enough space to squeeze it in the enclosure, that's what i did on my build.
I just had to put the relay bypass pcb inside some small plastic bag to isolate it from the main pcb.

Nope Relay Bypass kit, 10,40

Relay true bypass without microcontroller

www.musikding.de

 

[eh là bas ma]

I found what the 3PDT pads are, from my own debugging thread :

V

Post in thread 'Building a Black Eye : tubes daughter boards mistake, is it really bad ?'

Jan 12, 2024

If you can find a place to put it I don't see any reason it wouldn't work.

Switch pinout is, from left to right:

Input jack - Effect input - Ground - LED cathode - Effect output - Output jack

• vigilante398

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There's also the post where the circuit designer told me about the power requirements:

V

Post in thread 'Building a Black Eye : tubes daughter boards mistake, is it really bad ?'

Nov 30, 2023

Question number one is always what power supply are you using with it? Not giving the tubes enough current (the circuit requires 500mA or more) will negatively impact the sound. There's nothing wrong with Psvane ECC83, they should work fine.

• vigilante398

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[Audandash]

Yeah the other thing that stands out to me on that is the footswitch has a white outline where it would go. That’s usually on the side the switch/part is mounted on. It may work upside down but I don’t think it will work properly.

 

[jwin615]

300mA per tube is the consensus recommendation. Get a supply of at least 600mA.

 

[eh là bas ma]

It may work upside down but I don’t think it will work properly.

let's ask @jcpst , looks like he had the same 3PDT breakboard.
I suspect there are some other markings on the other side.

 

[eh là bas ma]

it's working

dont forget the Extra Bass Mode toggleswitch !

V

Post in thread 'Black Eye bass switch'

May 1, 2023

Is there any way to squeeze a toggle in above the PCB? Trying to remember how much room I gave you in that one, I'll have to take a look at one of mine.

Shouldn't be an issue running wires offboard to a switch, the cathodes aren't super sensitive lines.

You don't need a 3PDT or 4PDT though. The way I do it in my "Black Eye II" is actually to leave the 1uF caps in circuit and run the 47uF caps in parallel with them for 48uF. You can leave the negative end of the caps connected and just switch the positive end, so a DPDT is fine if you don't need an LED, or a 3PDT will do it if you want...

• vigilante398

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[jcpst]

let's ask @jcpst , looks like he had the same 3PDT breakboard.
I suspect there are some other markings on the other side.

Oh wow, I never noticed that I installed it upside down, even though there is a footswitch-sized white component outline printed on it!

The fact that I did this on two c2ce builds tells me it works both ways. I did a visual inspection of the traces and as far as I can tell it will work both ways. Pretty clever design.