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1968/69 Jazz Bass help me with the low output

pnchad

pnchad

Nov 3, 2005
2,814
1,263
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#1
I have a 68/69 J bass that's been confirmed as original pups & pots. It seems to be getting weaker & weaker, output wise the last few years. It sounds so good I don't want to replace anything. Anyone know the cause and if anything can be done?

thanks
 
#2
I'll take a guess: Alnico magnets fade over time and can be re-magnatized, I've read. Someone here knows more than I do, I'm sure, I've never done it. I was just reading about it recently though, can't remember where.
 
#3
There's some videos on youtube on recharging, StewMac also has free info on it: Invalid Link Removed scroll down to "CHARGE THE MAGNETS"
 
#5
it's actually unlikely to be the pickup magnets fading, alnico won't do that unless it's been hit with an external force like heat or other magnets.

more likely just problems with oxidation in the controls, or even something basic like setup; how close are the pickups to the strings?

what does sometimes happen with old pickups is that corrosion or rust gets down in the coil wires and breaks a wire, at which point the pickup becomes very weak with no low end; if that happens it's time to re-wind or replace it.
 
#6
Thanks all.

The bass sounds great just seems to have the weak output. If a winding wire was broke would it still work?

If it's oxidation in the controls how do you clean them? I've tried the spray stuff - never feel confident it's doing anything.

Obviously don't want to make changes.
 
#7
pnchad said:
The bass sounds great just seems to have the weak output.
Click to expand...
compared to what? have you tried it into a different amp, or different basses into the same amp? could be an amp problem, a bad cable, or even nothing at all.
pnchad said:
If a winding wire was broke would it still work?
Click to expand...
sort of, but it would sound really weak with no lows, and your tone knob would act like another volume knob.
 
#8
I've tried all the obvious things. Have many basses and amps. Excellent cables, etc. this bass was not played for a couple years and I started a new project where it's perfect. 6 mos ago it seemed stronger than today. About 60% of the output of a 76 P - most of my others are active.

Like I say it sounds wonderful. A 68 J, what's not to like? BTW it may have gotten hot at some point. I moved so...
 
#11
walterw said:
it's actually unlikely to be the pickup magnets fading, alnico won't do that unless it's been hit with an external force like heat or other magnets.

more likely just problems with oxidation in the controls, or even something basic like setup; how close are the pickups to the strings?

what does sometimes happen with old pickups is that corrosion or rust gets down in the coil wires and breaks a wire, at which point the pickup becomes very weak with no low end; if that happens it's time to re-wind or replace it.
Click to expand...

I agree with most of this except: To my knowledge, heat only effects the magnet when the heat is applied--- cool it down--- magnet comes back to life.
This is how the "magnetic switch" in the tip of a 100 watt soldering iron works.
 

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