Grounds on multiple pcb's in one enclosure

[DrVon]

So I'm moving my kliche mini into a protein pedal so three PCB in one enclosure. I'm pretty sure I just need the grounds from one pcb going to the jacks. In this case my middle pcb. I would leave the ground connections empty on the outside PCBs.

https://imgur.com/a/kFaKcb3

Thoughts?

 

[Robert]

As long as they're all grounded to a common ground somehow (eg: DC jack) then you shouldn't need to ground the jacks to each board individually.

If there were LFOs, digital circuitry, BBD clocks, or an extremely high gain circuit it might be a little more critical, but you should be fine in this case.

 

[bowanderror]

As long as they're all grounded to a common ground somehow (eg: DC jack) then you shouldn't need to ground the jacks to each board individually.

There are generally two approaches to grounding:

1. Star Ground - All circuit & jack grounds connect to the same shared ground point - like one jack, pot or PCB ground. All the ground connections "star outward" from this single point.
2. Daisy Chain - Ground is passed along from one circuit to another, but all connected in series to the same ground reference.

Builds that rely on being very low noise (like pro audio) or builds that have a bunch of subcircuits with different power & signal types often prefer Star Grounding. For guitar pedals, Daisy Chain grounding is fine. I find that a mixture of the two is usually the best approach, and doing a quick wiring sketch on paper will save you a lot of problem solving down the line.

Two things to avoid in your sketch:

1. Super long daisy-chains - This will increase the impedance to ground for circuits farther along the chain and may alter the relative ground reference voltage. Keep the amount of separate circuits attached to one chain as low as you can (2-4 ideally) and use star grounding to add more chains if needed.
2. Ground Loops - This is where the same circuit is attached to 2 separate ground references of different potentials, creating a loop. This can happens if you "over ground" a particular board or circuit, or reference the pots/jacks/switches to a different ground point in addition to the board ground.

 

[DrVon]

Thanks for the replies. Since the negative is grounded on the kliche that reference would then be consistent through out. Just wanted to make sure. Multiple ground paths are not typically optimal in control but I was unsure on the audio side of things. Thanks!

 

[Preverb]

Does this end up being any smaller than 3 separate 125b enclosures?

 

[DrVon]

Does this end up being any smaller than 3 separate 125b enclosures?

No it doesn't but I only use one power supply input that's the reason.

 

[Preverb]

No it doesn't but I only use one power supply input that's the reason.

Definitely an advantage. I've had multiple issues with noisey power supplies in the past so now I am looking at the Cioks stuff. Unfortunately, they don't seem to have that many outlets compared to some of the other ones.

 

[bowanderror]

No it doesn't but I only use one power supply input that's the reason.

You could always use a daisy chain DC cable if that's an issue. Or even add a second "DC Output" jack to pedals that have low current draw.