Weak 480 bridge pickup (.0047 mfd cap)

[patinmexico]

Hello there,
I recently picked up my 2nd 480, this one in azureglo, also 1975 as my über modded jetglo one. I traded one of my 70s Fender Mustangs for it, since i have too many of those.
It has had a headstock break/repair, owner told me it's fully original with only one previous owner.

Upon arriving i notice the bridge pickup sounding extremely weak and thin. No reading on the multimeter, either. Neck pickup is around 10,5k.
Wiring looks original to me, it has the .0047 mfd cap in it, though. When i bypass it with a cable, then i get a bridge reading of about 6,6k. What's going on, is the pickup damaged?



I've bought a HB-1 pickup now, so the original one is going out anyway. Is it best to remove the cap too, for the most powerful sound?

Any advice? Thanks!

Pat.

[kennyhowes]

Pic of the pickup?

[patinmexico]

Pic of the pickup?

Ok so I just went ahead and did it. Removed the original Higain (which still only reads slightly above 6k) and installed the HB-1. That one sounds much louder, but the difference between both positions is huge - it has basically no bass at all, and i still get no reading from the output.





So I'll go ahead and remove/bypass that cap and see what happens.
...but it's save to assume the original bridge pickup is broken, then?

Thanks!

[iiipopes]

Starting in the mid-70's, Rickenbacker went through a phase to get the maximum tonal contrast between neck and bridge pickups. This included overwinding the neck pickup to cut treble and underwinding the bridge pickup to bring out treble. This resulted in bright, but weak, bridge pickup volume and darker, but louder neck pickup volume, which to get any balance required trimming the 5th knob quite a bit. My 1980 320JG started out the same way: 6.5 kohm reading of the bridge (cap bypassed) and middle pickups, and @ 12 kohms on the neck pickup.

Oh - BTW - since a capacitor only passes alternating current (such as a string vibration signal), any ohmmeter measurement of a circuit with an in-line capacitor will always show open until bypassed.

[patinmexico]

Starting in the mid-70's, Rickenbacker went through a phase to get the maximum tonal contrast between neck and bridge pickups. This included overwinding the neck pickup to cut treble and underwinding the bridge pickup to bring out treble. This resulted in bright, but weak, bridge pickup volume and darker, but louder neck pickup volume, which to get any balance required trimming the 5th knob quite a bit. My 1980 320JG started out the same way: 6.5 kohm reading of the bridge (cap bypassed) and middle pickups, and @ 12 kohms on the neck pickup.

Oh - BTW - since a capacitor only passes alternating current (such as a string vibration signal), any ohmmeter measurement of a circuit with an in-line capacitor will always show open until bypassed.

oh wow, interesting, thanks!
So the higain with 6k might actually be alright after all?! Insane!

Considering my bands/musical style, it's not suitable though. So the HB is a good addition i guess. I'll report back with the result/thoughts after removing the cap.
Cheers!

[maxwell]

I'd experiment with the pickup heights (both PUs). That bridge PU foam spacer looks like it's pretty well compressed already, but a PU can be too close to the strings (magnetic pull decreases string vibration amplitude; volume). Lower the neck PU to make it "weaker" and maybe more in keeping with the bridge PU. Typically, adjusting relative PU heights is how I've delt with uneven volumes, but not on a Rick; there is not much room for vertical adjustment, but I haven't had the need to do so. But, hey, it may get better, or it may not; try and find out. It's pretty easy to do.

[patinmexico]

I'd experiment with the pickup heights (both PUs). That bridge PU foam spacer looks like it's pretty well compressed already, but a PU can be too close to the strings (magnetic pull decreases string vibration amplitude; volume). Lower the neck PU to make it "weaker" and maybe more in keeping with the bridge PU. Typically, adjusting relative PU heights is how I've delt with uneven volumes, but not on a Rick; there is not much room for vertical adjustment, but I haven't had the need to do so. But, hey, it may get better, or it may not; try and find out. It's pretty easy to do.

Thanks!
Yeah usually height adjustments might work wonders, but i believe here it's the cap that just takes out all the bass and makes the bridge shrill and too glassy...
We'll see.

[maxwell]

A lot of guys take those caps out or disconnect one end or bypass them. When I replaced the wiring harness on my 325v59, I also bought a .0047 mfd cap with the intent of including it. But after exploring the range of tonal adjustment without the cap yet installed, I could not imagine wanting any further “brittle” sound exaggeration, and did not install it. We’re looking forward to your post-op report.

[patinmexico]

A lot of guys take those caps out or disconnect one end or bypass them. When I replaced the wiring harness on my 325v59, I also bought a .0047 mfd cap with the intent of including it. But after exploring the range of tonal adjustment without the cap yet installed, I could not imagine wanting any further “brittle” sound exaggeration, and did not install it. We’re looking forward to your post-op report.

Yep quite excited/curious myself, since i can't use my other 480 as reference



...will i HAVE to bridge it with a cable or can i just snip off one end? Thnx

[patinmexico]

...oh and just for giggles, while showing off, here's my 450 - i believe it's a 74 or 75 iirc

[jps]

A lot of guys take those caps out or disconnect one end or bypass them.

Of the three choices you offer only one of them is valid if you still want the pickup to produce sound; bypassing the cap with a piece of wire shunted across the leads of the cap.

If you disconnect one end of the cap or remove it altogether the pickup will no longer be connected to the output of the guitar. There must be a direct connection between the pickup and the selector switch, either through the cap or through a piece of wire.

HTH.

[maxwell]

I am not going to quote you, jps, and further broadcast those bonehead suggestions I made....
Of course, you're correct. My excuse is that it was too early this morning, and my brain was not yet fueled by coffee.

IIRC, someone here years ago mentioned wrapping a piece of chewing gum wrapper foil around the cap, long enough to contact (connect, touch) the bare wires of the cap. Something like that would allow a correction without getting the solder gun out. What would you do? I'd try a piece of foil. I think there were other suggestions; I'll have to search....

LOL "...if you still want the pickup to produce sound..."

[jps]

I am not going to quote you, jps, and further broadcast those bonehead suggestions I made....
Of course, you're correct. My excuse is that it was too early this morning, and my brain was not yet fueled by coffee.

IIRC, someone here years ago mentioned wrapping a piece of chewing gum wrapper foil around the cap, long enough to contact (connect, touch) the bare wires of the cap. Something like that would allow a correction without getting the solder gun out. What would you do? I'd try a piece of foil. I think there were other suggestions; I'll have to search....

LOL "...if you still want the pickup to produce sound..."

No worries, mate!

I have read about the chewing gum wrapper story, too. I suppose this would be fine for "proof of concept", but even tightly wrapping a piece of wire around the two leads can be a long-term solution, so long as the wraps are truly good and tight. Soldering, of course, is always best practice, though.

[maxwell]

Yes, soldering in a short wire as a bypass would be the way to relatively easy to do and less disruptive. Easily removed if you change your mind. (Of course, if you find yourself changing your mind often, then install a push-pull pot.)

[patinmexico]

I am not going to quote you, jps, and further broadcast those bonehead suggestions I made....
Of course, you're correct. My excuse is that it was too early this morning, and my brain was not yet fueled by coffee.

IIRC, someone here years ago mentioned wrapping a piece of chewing gum wrapper foil around the cap, long enough to contact (connect, touch) the bare wires of the cap. Something like that would allow a correction without getting the solder gun out. What would you do? I'd try a piece of foil. I think there were other suggestions; I'll have to search....

LOL "...if you still want the pickup to produce sound..."

you guys