Ground loops in a multi-effects enclosure

[fingersoccer]

I'm in the final stages of designing an enclosure for a multi-effects unit and have come to the grounding stage. I'd like to avoid ground loops, but I'm getting a bit confused on what causes them. First, some specifics about the enclosure:

I'm building it in a Eurorack format, similar in style to a modular synth. The effect controls will be on vertical faceplates and the footswitches on a horizontal one, sort of like this:


I was planning on connecting the faceplates to the switchplate via a wire, as well as connecting the effect boards to the switchplate so that everything will share a common ground. Here's a side cutaway showing the grounding scheme for one of the effects:



I was always taught that wires effectively have zero resistance, so it seems like if the switchplate, faceplates, and effect boards were all connected together they would represent the same potential, eliminating ground loop hum.
My question is: does the drawing above qualify as a ground loop? And if I multiply this grounding scheme x12 (since there will be 12 effects in this enclosure), will this introduce noise into the circuit?

[ACS]

My understanding is: yes, that does qualify as a ground loop.  Follow the electrical path and see if it literally has a loop in it.

By moving the wire from the bottom of the faceplate to terminate at the stomp lug (where the other two are) you would be eliminating this, creating a basic star ground.

[defaced]

It depends on the details of what's on the board and how you're handling the input/outputs.  If the effects board does not have a ground connection to the face plate, then no, you don't have a ground loop with what you have drawn.  If the effects board does ground to the face plate, then yes, you have a ground loop.  ACS is correct in that the way to identify a ground loop is to literally trace the grounds and see if they form a circle.  If they do, then you have to decide which wire to cut.  If I had my choice, the one from the stop switch to the switch plate would be it, but that answer could change depend on what else is going on.  

A really good book that covers the real effects of grounding (and other things) is Tim Williams' Circuit Designer's Companion.  The Amazon preview has alot of the first chapter which deals with grounding, and offers examples of how to do exactly what you're doing.  It's well worth the read.  

http://www.amazon.com/Circuit-Designers-Companion-Second-Engineers/dp/0750663707/ref=sr_1_1?ie=UTF8&qid=1316691599&sr=8-1

I was always taught that wires effectively have zero resistance, so it seems like if the switchplate, faceplates, and effect boards were all connected together they would represent the same potential, eliminating ground loop hum.

Theoretically, this works great.  In reality, everything has some measure of resistance, capacitance and inductance.  These stray properties of the parts you use are what can cause serious headaches during design and build.  The actual wire resistance coupled with the current flowing through it will cause microvolt differences in the "grounding" path.  These small differences in potential are what cause problems when there's a ground loop.