2 effects in 1 enclosure

[POTL]

I want to assemble a dual pedal, in the style of Analogman King Of Tone or JHS Double Barrel
I have to create for each circuit my own power section (with filters and voltage dividers)
as in the image

Or can I use a common power section (including a voltage divider) for both circuits?
How is the way correct?

[vigilante397]

Or can I use a common power section (including a voltage divider) for both circuits?

Yup, assuming they use the same Vref (most do). Do that.

My firewall at work is blocking the image, so I can't comment on that yet

[GibsonGM]

Like Vigilante says...you can use 1 common power section if you like.   The usual two 10k resistors to ground (or whatever values given), a cap to ground at the their junction to create your Vref for both circuits.

If you do as shown in your drawing, which is perfectly fine, you will still need to make the voltage dividers for each circuit.  Unless one of them is VERY power hungry, one setup for Vref should work fine. 

You should not need the 47R/220u cap IF your power supply is clean.  If you are in doubt, go ahead and add that extra filtering, as it costs very little more than board real estate.

[POTL]

Hi
I remember your advice given to me earlier, just at hand there is no drawing program (I have a computer at home without the required software) and I took the picture from the Internet.
I was afraid that the circuits could interfere and wanted to create 2 separate power networks.
It turns out that the circuits will not interfere with each other, if they have a common section of power and vref?
If I remember correctly from Analogman King Of Tone the power scheme is common for both halves of the pedal, but there and the circuits are identical.
If there are different schemes, for example Muff and Screamer or Rat and Bluesbreaker, they will work normally from the general power section and the general vref?

[GibsonGM]

They should not interact provided you have a clean source of power (battery, a good wall wart intended for guitar pedals...).    I suppose for the sake of being very sure our power is ok, there is no issue with installing the 47R/220u right where the power enters each board, and then using two bias networks, if you choose.

Or, you could place one 47R/220u where the power enters the enclosure, then run your individual power wires to each circuit.   It really is more a matter of how you built your effects.   I sometimes use 2, 47R/220 type filters if I have 2 separate PCBs inside a pedal, just because this is simpler...but I also have run 2 distortions in one enclosure, same power supply, with NO additional filtering.  Just the 2 bias networks, one on each PCB.  I have not had any problems, since they do not demand rapid changes in current.

If you build two effect on one PCB, then one 47R network would be OK, simply because the wire run you need to reach each effect's power points will not be as long.

The purpose of the filter really is to 'protect' a little against sudden demands for current from a circuit.  "Interaction" in the power supply is generally that one circuit is calling for more current, which 'steals' from the other circuit.   Typical things like distortions, overdrives...will not make this demand.  A tremolo or flanger, phase, maybe delay...might, because they work by oscillating and causing fluctuations in what they need for power, and are driving LEDs and so on.    I am not clear about which Analogman King of Tone circuit you are building (?)  I looked this up and found reverb, delay and distortion that have the same name...

If you feel like being SURE, then include it. Your choice     It will not hurt to have extra filtering, much as sometimes we add a small pF cap at the input to protect against RF that we may never encounter...I would opt for 1 470R/220u power input filter, and 1 bias network IF that does not require you to run wire all over the place to reach both circuits.

[vigilante397]

I agree with everything above. It shouldn't create any problems for multiple circuits to share the same power section. It also shouldn't create any problems to have an independent power section for each. It's completely your choice.

[GibsonGM]

If it's a delay (like I said, not sure), I'd make sure where the power enters the PCB for it, to use that 47/220u, just as a precaution.   Otherwise...yeah, little worry.

[POTL]

Thank you
I'm only interested in distortion pedals.
I was afraid that there might be some kind of interference with a common network, or a signal from one circuit would get into the second circuit.
2 filters seemed to me better, since there will be independent power networks, but the disadvantage is that the additional power network takes up space on the board, which is a disadvantage.
I gave examples of King of Tone and JHS Double Barrel as close pedals, to what I want to collect =)
If you say that there is no need to create separate power networks for each circuit, then I will create one general =)
Thank you for your answers!


I have already developed some boards ready for assembly, but for the future I want to ask one more question.
3pdt circuit, how practical to ground the input when the effect is in bypass mode?
I use the classic way


way with the grounding of the input I've seen from many manufacturers, is this way better than classic?

[GibsonGM]

Grounding the input is used by many, with good results. I tend to agree with this, as it really DOES silence whatever circuit it is applied to.  I often do not use it, but I probably should 

[vigilante397]

That is exactly how I wire every single pedal I build (but upside down for some reason )

[antonis]

I should propose some extra switch wiring



to sleep in peace in case of output cap NOT grounded via Volume/Level pot..


I should also propose the use of "pre-formed" solid-core wires (like those used for board jumpers) between switch lugs for easy soldering..

[suryabeep]

Antonis - that is soooo satisfying man...