• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

HOW COULD THIS HAPPEN?

Nomad98

Nomad98

Dec 13, 2005
626
112
Minneapolis
#1
Ok, so I have a 72 Jazz bass. The bridge pickup was not working. The tone control was working like a volume control but it was wired correctly. I was searching TB for answers and was assured that when your tone begins to work like a volume, you have a bad pickup. Like the coils corroded or broken.?.

I decided to get a set of DiMarzios and put those in the Jazz. They sounded super! I played it for a week or two and was really getting into the fact that I had both a neck and bridge pickup that could be soloed. That hadn't been the case for years as the bridge pickup that was in it hadn't much output for years.

Well, after a week of not playing the Jazz, I picked it up this morning and the bridge pickup was almost dead? WHAT! HOW COULD THIS HAPPEN? SERIOUSLY, I AM GOING TO LOOSE MY MIND. IT IS WIRED CORRECTLY! I HAVE CHECKED MULTIPLE TIMES, PLUS IT WAS WORKING A FEW WEEKS AGO. PLEASE HELP ME BY EITHER TELLING ME HOW TO FIX THE BASS, OR SHOOTING ME AND PUTTING ME OUT OF MY MISERY (who ever does the later can have the bass I suppose but I am really hoping for the "fix bass" option)!

I am using the original 250k pots and the DiMarzios are the humbucker Model 123's. They say you should use 500k pots but you can use 250k too. right? It did work after I wired it with the 250k's...

Thanks for any help or insight into this problem.

Phil (Nomad98)
 
#5
I didn't replace the pots. I switched the neck volume and the bridge volume and they acted the same way. Then I switched the volume and tone. They acted the same way... but I never replaced them. (by same way I mean that the bridge pickup has low output)

That was with the old pickups... The Dimazios worked for a few weeks? Now they are acting like the old pickups did.
 
#6
If the bridge pickup is hardly working (I'm assuming it sounds thin?) and the tone works as a volume, that means you have an open coil. This is common on Fender pickups, especially from the 70s. It's generally caused by corrosion where the coil touches the magnets.

Even though the coil is open, because the turns are capacitively coupled, you get some sound. If you check the pickup on an ohm meter it will read as an infinite circuit, or in the megohms.

Another thing to check is that that the connection to the coil at the rivets is good. Sometimes reheating those connections helps.

But it sounds like the pickup needs a rewinding.
 
#12
Sounds like it could be a short. A short at (or in) the cap could make the tone control operate like a volume control.

I'm thinking the original problem was a short. Replacing the
original pickup may have moved a component around enough
to make the short disappear -- but only temporarily.

This is pure speculation but worth considering as you look for
the problem.
 

Latest posts

Top Bottom
Back