Mod Ceasar Chorus with stereo blend

[Ralfonso]

Hi everyone,

I recently built a ceasar chorus. I am quite satisfied with the results - but...
My plan is to use a decent chorus to widen the stereo image of my guitar sound. Classical chorus pedals do this, as far as I know, by modulating only one side, while the other is unchanged.
My plan was to build something more flexible. Since the ceasar chorus has a blend poti, my plan was to split the signal and add a second blend poti.
Here were my plans:





The result is not satisfying at all. So I need some help

- I somehow, I broke the bypass completely. No signal is coming through anymore.
- If switched on, the Mono Signal works as usual, the Stereo Signal is very quite and I have the feeling that my new blend knob does not work either.

After some googling, I assume that I am missing a buffer?!

Does anyone see a chance to get this running? Or do I have to follow a complete different apporach?

Greets Ralf

 

[Robert]

Can you post a pic of your actual wiring?

I don't see any reason that your schematic shouldn't have worked as planned, aside from the fact that you won't be able to bypass both channels without some modifications to the offboard wiring.

The Binaura and Double Pendulum use a 4PDT footswitch + millenium bypass circuit to achieve stereo true-bypass switching with an indicator LED.

 

[Ralfonso]

Hello,

thanks for the quick reply.
Here are the wanted photos...

What is a millenium bypass circuit? Is there a pcb available for this?
As far as I undertand so far, I have to buffer a signal, when splitting it to stereo so that I do not loose volume, right?

 

[Robert]

You're doing MONO IN, STEREO OUT right?

If so you don't need an additional buffer, the signal is already buffered by Q1 before the split.

You also should be able to get by with a 4PDT footswitch and no millenium bypass since you aren't switching two input signals.

 

[Ralfonso]

Yes. I would like to have MONO IN and STEREO OUT.
Bypass: The dry input signal should be equally splitted to both outputs without loosing level.
On: The wet and dry signal shall be splitted and blend-able by two independent potis.

Since you say that my plan should workin principle: Any tips how to approach the trouble shooting? I never did this before...

Ok, after you hint with Q1, I understand that the wet signal is already buffered.
But in bypass mode, I need to split the signal too. So I would need a buffer there as well, right? Or do you suggest to get the dry signal from somewhere after Q1? If yes: from where exactly?

Thanks for your help so far.

 

[Ralfonso]

I did some checks so far...
Got the same voltages on IC2 as on my additional IC (PIN 5-8). Is it normal that V- (PIN 4) has 0.00V? I have this on both ICs
If I compare the resistance values over each resistors, I get identical values.
Hmm. Really need some ideas...

 

[Robert]

Take your buffered bypass signal from the output of Q1.

It's already buffered right there, just split it to the two outputs bypassing the rest of the circuit.

 

[Ralfonso]

Ok thank. Will do that.

I still cannot find, why my additional path does not work.
To repeat myself:
Got the same voltages on IC2 as on my additional IC (PIN 5-8). Is it normal that V- (PIN 4) has 0.00V? I have this on both ICs
If I compare the resistance values over each resistors, I get identical values.

Any ideas?

 

[Ralfonso]

Hi All,

I made some progress! Unbelievable, but unfortunately, also a bit embarrassing. The root cause of my problem was that the delivered plug was not a stereo plug. It was a mono plug with a switching contact. I did not check this, because it had 3 pins...
So I finally get a stereo signal - cool.

Unfortunately, both stereo blends do not work independent from each other.
I assume that the root cause is that both potis influence each other as some kind of voltage divider.

Do you have any tips how to get them independent?

Greets Ralf