5-string "P-Bass" pickup question

[fishtx]

Got a question for you pickup gurus out there.

Are there known grounding or phasing issues with 5-string "P-Bass" style pickups since they are split unevenly (ie 3-poles on the top side of the pickup, and 2 poles on the bottom side)??

I've got a 5-String CS Reggie Hamilton that has a lot of hum off the "P" style pickup (2-pole side) when I touch it. If I touch the 3-pole side, no hum.

If I complete the ground loop (through my body) by touching the pickup with a finger of my right hand, and the strings on the neck with my left, the hum stops.

I thought there may be a bad ground somewhere. I have opened it up and gone over it but can't find any loose or broken grounds (bridge ground is good, etc).

Note there is only a single ground coming from the "P" pickup (off the 3-pole side...which does not cause the hum...hum only when I touch the 2-pole side).

I hope this makes sense.

Thanks.

 

[nukes_da_bass]

According to how i understand these things (which is poor at best), a P pickup is actually two pickups wired in series hence creating ONE split humbucking pickup. No noise should come if it is wired properly.
I suggest you contact FMIC and ask them
For two wiring diagrams- one for the pickup itself, and one for the entire preamp.
It is at all possible the pickup itself is wired incorrectly.
I bet replacements are available aftermarket, i got a deluxe 5 P from a vendor i found here at TB.

 

[mazdah]

Both my 4 string P-basses hum like crazy when I touch any pole piece of pickup (no matter which side)

 

[Fuzzbass]

There is nothing about a five-string P-bass pickup specifically that should contribute to hum. Note: many humbucking soapbars designed for five string basses are similar in that they are side-by-side split coils, one covering three strings and the other covering two.

As noted by others, have the wiring checked. Also... avoid touching the poles. That's a downside to exposed-pole pickups. It is weird that it happens to one coil but not the other, though.

 

[fishtx]

It is weird that it happens to one coil but not the other, though.

Yes...that's weird...

 

[J-wall]

Try the pickup forum, nice and knowledgeable guys there. And, yes, there are issues with a 5 string P pup but I am not be best to explain it. More of a balance between the two "halves" but maybe hum issues as well.

 

[fishtx]

Try the pickup forum, nice and knowledgeable guys there. And, yes, there are issues with a 5 string P pup but I am not be best to explain it. More of a balance between the two "halves" but maybe hum issues as well.

Thanks...

 

[RawOrange]

I know, old thread, but I am having this issue and it wasn't really "solved"

Same thing is happening to me, except the pickup is a regular four string P-Style. Only one coil has the crazy buzz, and the other is fine. It is alleviated when I touch the back of the volume pot or other ground, but otherwise it is unusable. Any insight would be greatly appreciated!