J-Bass Wiring Issues - Bridge Pickup Silent

[Gideon K]

Hey folks,

Need a bit of help or advice. I seem to have screwed up the wiring or something on a bass of mine. It's a dinky Aria DMB 380 bass, with pots and pickups wired like a Jazz Bass - two single coil pickups, volume knob for each and a master tone knob.

It sounds ok on the neck pickup but I wanted to experiment with putting this EMG pickup (passive) in the bridge since I had it lying around. I made a diagram of how the original was wired - black and red leads coming from the original pickup, black going to the back of the pot, red going to middle hoop thing on the side of the pot. Since there weren't any instructions as to which wire was which on the new pickup, I tried it one way and that turned out to be wired backwards/out of phase, so I went about unsoldering the two leads and trying them the other way around. This time no sound was coming out of the bridge pickup at all. The neck was working fine.

Couldn't figure out what was what, spent ages screwing around trying to find the root of the problem, tried changing it back to the original pickup but still, no sound from that position whatsoever. Seeing as neither pickup makes sound I don't think the pickups are the problem. Any ideas as to what I could have done wrong that has killed the signal? I'm really not sure what it could be since the neck pickup wiring has to go across the back of the Bridge volume pot to get to the input jack, so what gives?

 

[ginormous]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

Welcome, Gideon. Hope you enjoy life here in the SD forums.

It's entirely possible you may have cooked the volume pot with the unsoldering and re-soldering. It happened to me, when I was building a frankenstrat.

Even if you've got a relatively low-wattage soldering pencil (15 watts or so), too much heat at the solder joint can and will short out a pot.

Get a voltmeter and see if signal will pass through. Test each component individually, and then the circuit as a whole.

 

[Gideon K]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

Hi ginormous, thanks for that. The thought did occur to me. I've got a multimeter on its way in the post, so will get back about that.

The only thing is, the neck pickup is working fine as before and it is only connected to the rest of the circut by being soldered to the back and side of the bridge volume pot, so presumably the current has to pass through that volume pot too?

 

[jeremy]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

the back of the pot is just metal and usually used as ground. if you could post a good quality detailed pic of the wiring we might be able to help more effectively

 

[Mincer]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

I would also just check the bridge pickup alone to make sure it is still working: wire it right to the jack. I agree on posting some piics, also..it is very helpful in figuring these things out.

 

[Gideon K]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

My camera isn't working at the moment, but here is a diagram of the wiring except I don't know what the value of the pots are, and I don't know the value of the capacitor on the tone pot. It is dark green with 2A683J on it. Otherwise pretty much identical to a Jazz bass except the neck pickup pot is the one with the ground connected.



I'll try the bridge pickup wired to the jack and get back to you.

 

[jeremy]

Re: J-Bass Wiring Issues - Bridge Pickup Silent

that drawing looks fine, but they usually do the neck signal isnt going through the bridge volume pot at all. even if the wires are connected to it. the ground is using the case and the hot is going right to the wire going to the tone control.

check the bridge pup to the jack, if that works then either the pot is bad or the wiring at the pot is bad. luckily its a simple circuit so shouldnt be too hard to track down the issue!