To Star or Not to Star?

[DavyDave53]

Is doing a star ground inside a guitar worth it? 

Or will the extra wire just increase the sensitivity and range of the guitar's "internal antenna"?

 

[bagman67]

I haven't been at it all that long in the grand scheme, but I've actually found it rather convenient to take a lot of ground wires and tie them together with a wire nut.

 

[Dan025]

the whole idea of the star is to prevent ground loops but many people say it's not a problem, the loops are too short to be in the audible spectrum... so can you get awat with not doing it? sure. but if you shield the cavity it negates the whole point, even if the point is pointless according to some so some will insulate the shielding from the pots to ground them differently. that's probably a few steps too far. if you want to follow the popular wisdom around here and use grounding rings and no or minimal shielding with shielded cable then some version of a star, or daisy chain or combination of those isn't really a hassle.

 

[line6man]

"Star grounding" is the epitome of pointlessness and misunderstanding. You cannot form a significant ground loop in a guitar.

 

[Cagey]

What he said ^

 

[DavyDave53]

Well that answers that then.

Less is more, except where more is more...

 

[Jumble Jumble]

Your guitar is already star grounded: the centre of the star is the sleeve contact on the jack.

The "ground loop" thing in guitars seems to come from people thinking that a "ground loop" is a closed loop made of grounded metal. Which would mean that if, for example, you grounded a coin, that would be fine, but then if you drilled a hole in the coin, you'd have a ground loop. It's ridiculous. Just ground everything according to how easy it is to do, how easy it is to undo, and how tidy it is.

 

[swarfrat]

Agreed - not necessary in a passive guitar.

All wires, even chassis metal, has resistance. What Star Grounding attempts to avoid, is the daisy chaining of all those resistances. In particular it attempts to avoid having "ground" for a high gain section riding on top of the voltage gyrations induced by a high current circuit dumping a bunch of current into the same resistance.

In a guitar you have miniscule currents running around, very short wires. 

 

[mayfly]

Just joining in the chorus here.

You only have to worry about ground loops when you have significant currents flowing in ground paths.  Then you have to think about impedance of those paths and voltage differential between grounded points and what noise that can inject into high impedance audio circuits.  Important in a guitar amp, REALLY important in a recording studio, but not in a guitar.

 

[swarfrat]

If you need a whip to beat the equine carcass...

I built an amp in college, and I star grounded EVERYTHING. The ground lug had about 2 dozen copper wires 6-18" long radiating out from it in perhaps one of the best thermal dissipators ever made.  I had to borrow a this big heavy soldering iron (meant for stained glass windows I think). The solder blob just laughed maniacally at anything less, including high power but low mass soldering guns.