Bass Grounding Help

[Wxp4759cb]

I am trying to fix what I believe is a grounding issue on one of my basses. It has a loud electric hum which abates most of the way if I touch the control plate with my fingers. I've attached a video to demonstrate. I've also attached a pic of the inside of the control panel. I've looked around and don't see anything obviously loose. Any suggestions on where to look would be appreciated. Thanks

 

[Spidey2112]

When did the problem first rear it's ugly head?

* Good job, uploading a video to help analyze the problem, too.

 

[Wxp4759cb]

I received the bass yesterday and it already had the problem then. It didn’t a few weeks ago when I tested it out at a store. So maybe something came loose in shipping. I can return the bass still, but if it is a simple grounding issue I can fix I might prefer to fix it myself.

 

[Spidey2112]

I'm good with that, as long as it doesn't void any warranty/return policy... the good ones will know if you were in there, or not.

 

[FunkHead]

There’s an empty ground pin on the one module.

 

[Wxp4759cb]

I haven’t touched anything inside so far. I figure I’m allowed to open it and just look with my eyes since that’s where the battery is.

 

[Spidey2112]

Same result touching other components? (i.e. bridge, strings, jack)

 

[Wxp4759cb]

Pretty much only touching the control plate does it. Like I mentioned I haven’t been stabbing around inside the bass so it sure if touching something in there would do it. Touching the strings makes no difference.

 

[Spidey2112]

I haven’t touched anything inside so far. I figure I’m allowed to open it and just look with my eyes since that’s where the battery is.

Lol! The good ones will know if you changed the battery.

 

[Spidey2112]

Is the cavity shielded?

 

[FunkHead]

I swear that looks like an EMG pre. What are the details of this bass?

 

[Wxp4759cb]

Yeah prob true. The dealer said I could return it or take it to a tech of my choice so I don’t think they will mind necessarily, but I will email him again before trying to actually change anything.

Funkhead, can you be more specific where you are looking that you see that?

 

[Wxp4759cb]

It’s a Sadowsky pre. I was trying to keep my statements generic though to not throw anyone under the bus.

 

[FunkHead]

Yeah prob true. The dealer said I could return it or take it to a tech of my choice so I don’t think they will mind necessarily, but I will email him again before trying to actually change anything.

Funkhead, can you be more specific where you are looking that you see that?

It says Emg on it right near the empty lug that says gnd

 

[Wxp4759cb]

I see it now FunkHead. Any idea what, if anything, should be connected to that?

I think the wiring diagram is at [Invalid or Expired Link Removed]

 

[Wxp4759cb]

Is the cavity shielded?

Yeah, I believe so. It looks like it at least.

 

[FunkHead]

I see it now FunkHead. Any idea what, if anything, should be connected to that?

I think the wiring diagram is at [Invalid or Expired Link Removed]

That’s not the pre in your bass.

 

[Wxp4759cb]

Looks like there should be a black ground cable going to it from the push/pull 250k tone knob if I am reading the diagram right

 

[Wxp4759cb]

That’s not the pre in your bass.

Well, that explains why the diagram didn’t make sense at least lol

 

[FunkHead]

Honestly just ask Roger to help you get it sorted.