Ground the output jack, waht exactilly means?

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Ground the output jack, waht exactilly means?

boratto
I see someone post about:
Ground the output jack on the Dunlop Q Zone, to reduce noise.

What exactly does it means? How to do it?

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Re: Ground the output jack, waht exactilly means?

dexxyy
you probably already do it, it`s just a ground wire from the output jack sleeve to ground. some people don`t bother wiring the ground on the output jack cos they figure that cos the input jack is grounded and is connected to the metal enclosure which is connected to the output jack that that is grounding the output. Personally I always ground the output jack, that way if the jack ever works it`s way a little loose it is still always grounded.
If it wasn't for this website I would definitely have a life.
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Re: Ground the output jack, waht exactilly means?

IvIark
Administrator
Me too
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Re: Ground the output jack, waht exactilly means?

inefficiency
I'm on the fence about it (mainly dude to lack of knowledge).

I kinda feel like you should because the enclosure might not be the best conductor in the world and having an actual wire there seems like the "proper" way to do it.

However, I heard that you can have problems if there's more than one direction that the juice can go. Like if you have one route shorter than the other when grounding you can get issues, so you should daisy chain them all or at least make sure there is only one route to ground. So in this example, the jack is grounded via the enclosure and if you add another cable then it can possibly get there quicker via that route and cause issues.

This is just stuff I've heard and is probably false or irrelevant in this scenario, but I guess it's food for thought. I'm also shit at explaining, so I hope that made sense.
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Re: Ground the output jack, waht exactilly means?

induction
The enclosure is a decent enough conductor, but dissimilar metals have a tendency to build up a layer of oxidization when they are held together. This oxidization layer can block current flow, which is another way you can lose your ground connection in addition to the jack working loose.

In principle, multiple paths to ground will create a ground loop, and any time-varying magnetic field (like those caused by fluorescent lights, computer monitors, air conditioners, and the rest of your gear) can generate current in those loops, that will manifest as noise in your circuit. So the absolute best way to ground the enclosure and jacks is to have the ground tab of only jack shorted to the enclosure. The other jack will be isolated from the enclosure and the ground tab will be star grounded to the first jack along with all other ground points. This allows you to use the grounded enclosure to shield the circuit from electromagnetic noise without creating any ground loops.

In practice, ground loops inside pedals are almost never a problem, so you can just ground both jacks to the enclosure if you want, but you should still include a wired ground connection to avoid problems. You'll get far worse noise problems from improper lead dress than you'll ever get from ground loops inside a shielded pedal. So you'll get more mileage by spending your time and attention on making sure your output wires are nicely separated from and not parallel to your input wires, and that the negative legs of your power filter caps are as close as possible to the adapter ground.

The biggest problems are in circuits like the Vox Repeat Percussion or LFO circuits, which fire a large amount of current to ground at regular intervals. If this current runs through a ground pathway that is connected to components in the signal path, it will temporarily change the voltage of the signal ground wire, and you'll get audible ticking. In this case, you'll want to make sure that those kinds of noise sources have their own dedicated ground path that leads directly to the adapter ground, which will be the only point where it contacts the signal ground. This keeps the extra current bursts and associated voltage spikes contained in the LFO ground wire and keeps signal ground stable and quiet. I think this is what inefficiency was referring to above.
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Re: Ground the output jack, waht exactilly means?

inefficiency
Yeah, the ground loop thing was what I was referring to. Nice to know I was at least on the right track!

Great additional info there though! I've heard lots of people complain about pedals "ticking", but I've never experienced it myself and hopefully now I never will because I know at least one cause of it!

Thanks for the excellent information!