Shielding

[Koop]

Question for those with expertise...will a shielded wire cause a ground loop if you ground the shielding on the chassis away from the pre-amp ground point?

[Phil_S]

Only ground one end of the shield, doesn't matter which end. Ground to any convenient chassis point, not to the circuit ground. Essentially, it is an extension of the chassis.

If you ground both ends, well, it's a loop!

[Koop]

Thanks for the reply. That's what I thought but I wanted confirmation before continuing my build. Thanks again.

[kwijabo]

first, yes - only connect one side.

second - i think it depends what grounding scheme you are using. if you're using switchcraft jacks you automatically ground to the chassis at the entry point just by using that style of jack.

i use marshall style jacks and attach the ground to the V1 circuit ground. the reason is that in any circuit, when the current reaches ground it has to get back into the circuit. keeping the ground of your guitar and pre-amp stage 1 together and isolated from other parts of the circuit ensures that the other circuits' effect(s) on the ground do not tie into the pre-amp or your guitar. someone correct me if i'm wrong.

http://www.freewebs.com/valvewizard2/Grounding.html

page 12 of that pdf.