grounded twice?

[dirkscalling]

Have an SX Vintage Style p/bass and it has a ground running from the tone pot to the bridge ,, I' shielded all the cavities, still getting a buzz without touching the bridge or strings etc.... should or can I run another ground from the input jack to the bridge?

 

[abarson]

Use an ohmmeter to measure the ground between the bridge and the output jack: it should show continuity with no resistance.

 

[dirkscalling]

di

Use an ohmmeter to measure the ground between the bridge and the output jack: it should show continuity with no resistance.

 

[dirkscalling]

did that and it buried the needle!!!!

 

[Ronzo]

You mean continuity (zero ohms) or an open circuit (infinite ohms)?

 

[dabbler]

Are your shields tied to ground? And do they make contact with the pickguard shield?

 

[dirkscalling]

Are your shields tied to ground? And do they make contact with the pickguard shield?

 

[dirkscalling]

yes and the whole pickguard is shielded

 

[dirkscalling]

You mean continuity (zero ohms) or an open circuit (infinite ohms)?

 

[dirkscalling]

infinite ohms

 

[Ronzo]

infinite ohms

I suggest that you re-run the ground connection to the bridge. Maybe use a larger wire gauge for better durability.

 

[dirkscalling]

I suggest that you re-run the ground connection to the bridge. Maybe use a larger wire gauge for better durability.

 

[dirkscalling]

should i run from the tone pot or the input?

 

[Ronzo]

should i run from the tone pot or the input?

I usually find it best to terminate all grounds at a single point, if it’s easy to do so. Not essential, but it’s best practice. Google “star grounding”.

EDIT: [Invalid or Expired Link Removed]

 

[gumtown]

You should connect to the pot back-shell which is also connected to the signal ground.
It is fine grounding everything, but they all need to also be connected to the input jack ground too.

With your ohm meter, if you connect the two test leads together, the reading it shows should be similar to the continuity checks in your bass.

 

[40Hz]

I usually find it best to terminate all grounds at a single point, if it’s easy to do so. Not essential, but it’s best practice. Google “star grounding”.

EDIT: [Invalid or Expired Link Removed]

You could if you wanted to. But star grounding is overkill on a circuit like those found in a passive bass. A lot of times it just adds to the amount of wire in the cavity with no measurable benefit since ground loops aren’t an issue. As long as there’s a solid ground path from the tonestack, shielding, and bridge to the jack’s gound lug, you're sufficiently grounded. It doesn't matter if there’s multiple paths or just one.

 

[dirkscalling]

m

You could if you wanted to. But star grounding is overkill on a circuit like those found in a passive bass. A lot of times it just adds to the amount of wire in the cavity with no measurable benefit since ground loops aren’t an issue. As long as there’s a solid ground path from the tonestack, shielding, and bridge to the jack’s gound lug, you're sufficiently grounded. It doesn't matter if there’s multiple paths or just one.

 

[dirkscalling]

my bad read the meter wrong o ohms.... good?

 

[ThingsAbove]

Yes zero Ohms means you have continuity across the various components that need grounding. You can still have a hum if the pickup and control cavities are not shielded and tied together on the common ground.

 

[dirkscalling]

put some shielding under the bridge and all hum is gone,,,, thanx to all or the help ... love this group,,, i count myself wiser from all the input !!