Can someone check my block diagram (parallel mixer - JMK paralyzer content)

[LaceSensor]

Hi

I have been asked to design a pedal. The general requirements are two dirt circuits in parallel, with a reverb in front of one of them.
There should be the option for each of the effects to be turned off to create combinations. There should also be the chance for a clean blend option, as the pedal will be used on bass.

I remembered I had PCB for a tool from JMK called the  Paralyzer which I felt would work perfectly.
I drew up this block diagram for the client but wanted to sanity check it with you. Obviously I took the block diagram from JMK manual and modified it crudely in paint to get the point across.



The idea is to keep it simple with three manual toggle switches to define the sound structure, with a single stomp switch for global bypass. In a way its similar to the JHS VCR I suppose. He also doesnt want lots of lights etc so just one bpass one LED.

The concept is to have a RAT as the main distortion, with something else in the other fuzz, something simple like a 1 knob fuzz perhaps. Any suggestions there would be cool!


So, will this work? Any thoughts or comments? Am I crazy?
I dont want to take on the project and not have it work and be unable to deliver as its on a time scale to get it done.

cheers

Ian

[Aentons]

It looks like the "Other Fuzz" will have to be off if you want clean blend. I would split the input 3 ways so the clean is independent.

[matmosphere]

Just thinking out loud but, in order to do a clean blend shouldn't the blend circuit be before any of the effected signal? I also think you'll need something to combine the parallel signals to a single output.

[matmosphere]

This might be a little over complicated, but I think you could still just use a switch for each effect and have the blend circuit in front of everything. I think when the effects are all off it would just blend clean signal in with clean signal.

It might be most useful to have individual blends for each path (each following the splitter) but it would make it harder.

[LaceSensor]

Hi

Yes in order to have the claen blend "other fuzz" has to be off but thats apparently fine.

I dont want to have to get extra complex really, the whole point is to have two parallel distortions.

The Paralyzer PCB should sum everything back to one output.

[Aentons]

Hi

Yes in order to have the claen blend "other fuzz" has to be off but thats apparently fine.

I dont want to have to get extra complex really, the whole point is to have two parallel distortions.

The Paralyzer PCB should sum everything back to one output.

I think you guys are saying the same thing, just showing it a little differently. "Blend circuits" usually consist of two parts, a buffered splitter, and a buffered mixer.

If it's clear to your customer that it's clean OR fuzz and there is no option for clean AND fuzz, then you are good.

The only other thing that I would consider pointing out is the potential effect that the buffer would have on the fuzz

[jkokura]

Hi

Yes in order to have the claen blend "other fuzz" has to be off but thats apparently fine.

I dont want to have to get extra complex really, the whole point is to have two parallel distortions.

The Paralyzer PCB should sum everything back to one output.

I think you guys are saying the same thing, just showing it a little differently. "Blend circuits" usually consist of two parts, a buffered splitter, and a buffered mixer.

If it's clear to your customer that it's clean OR fuzz and there is no option for clean AND fuzz, then you are good.

The only other thing that I would consider pointing out is the potential effect that the buffer would have on the fuzz

Yep, this is the thing.

I've gotten good feedback in general, but the one thing I often hear from people on the circuit (which isn't my design by the way, it's RG Keens - I just made it a PCB with a couple small adjustments) is that it doesn't play well with two circuits that phase cancel. I chose to make it the way it is without adding a switch. At the time, I ran as many circuits as I could in parallel, dozens at least, and I couldn't come up with any that actually had problems. A few combos have come up over the years (6 or so) I've been selling the PCB.

All that said, yes, this is what it's designed for. It should work as you want it to.

Jacob

[LaceSensor]

Hi

Yes in order to have the claen blend "other fuzz" has to be off but thats apparently fine.

I dont want to have to get extra complex really, the whole point is to have two parallel distortions.

The Paralyzer PCB should sum everything back to one output.

I think you guys are saying the same thing, just showing it a little differently. "Blend circuits" usually consist of two parts, a buffered splitter, and a buffered mixer.

If it's clear to your customer that it's clean OR fuzz and there is no option for clean AND fuzz, then you are good.

The only other thing that I would consider pointing out is the potential effect that the buffer would have on the fuzz

Yep, this is the thing.

I've gotten good feedback in general, but the one thing I often hear from people on the circuit (which isn't my design by the way, it's RG Keens - I just made it a PCB with a couple small adjustments) is that it doesn't play well with two circuits that phase cancel. I chose to make it the way it is without adding a switch. At the time, I ran as many circuits as I could in parallel, dozens at least, and I couldn't come up with any that actually had problems. A few combos have come up over the years (6 or so) I've been selling the PCB.

All that said, yes, this is what it's designed for. It should work as you want it to.

Jacob

Hi Jacob thanks for your validation. Im going to check the inteded circuits and see, worst case I have to add a phase switch in there too.

cheers all

Ian

[LaceSensor]

Just to check

Assume the reverb and RAT are on, and the "other fuzz is off" will that allow clean to be blended in? Yes or no?

thanks

Ian

[matmosphere]

Ah, sorry I totally glazed over the part about the paralyzer circuit. Makes total sense now.

[Aentons]

Just to check

Assume the reverb and RAT are on, and the "other fuzz is off" will that allow clean to be blended in? Yes or no?

thanks

Ian

Yep

[LaceSensor]

Just to check

Assume the reverb and RAT are on, and the "other fuzz is off" will that allow clean to be blended in? Yes or no?

thanks

Ian

Yep

cheers buddy

If I added a clean blend to the "otherfuzz" I could have clean on that too I suppose

[LaceSensor]

anyone know for sure if I will get phase issues with the Rub-a-Dub reverb?

Seems it uses a Dual op amp and the signal goes into the "-" side rather than the "+"

The distortion pedals I am considering seem to use the "+" side....

Im a strong noob when it comes to phase cancellation queries...

[jkokura]

anyone know for sure if I will get phase issues with the Rub-a-Dub reverb?

Seems it uses a Dual op amp and the signal goes into the "-" side rather than the "+"

The distortion pedals I am considering seem to use the "+" side....

Im a strong noob when it comes to phase cancellation queries...

Me too, I'm terrible with that sort of thing. I design with my ears, and I'm not very good even then. The way I would find out is actually trying it, which isn't super helpful, so perhaps someone else has the answer.

Jacob

[Aentons]

anyone know for sure if I will get phase issues with the Rub-a-Dub reverb?

Seems it uses a Dual op amp and the signal goes into the "-" side rather than the "+"

The distortion pedals I am considering seem to use the "+" side....

Im a strong noob when it comes to phase cancellation queries...

If it goes in a - input an odd number of times it's inverted, if an even number it's not

Edit: I checked the schematic, it is not inverted