Hello, I have a bass tech question You're welcome to ask me computer questions in return!
I just put nylon tapewound strings on my P-Bass, which is fitted with SD Antiquities pickups. Every time I touch a pole piece on the forward pickup (i.e. the one closer to the neck), I get a loud "zzzttt" coming through the amp. This was not the case with all-metal strings. The rear pickup doesn't make the noise when I touch the pole pieces.
tapewound strings have an inherent problem with grounding. with metal strings, the you provide a nice ground for the electronics, but the tape acts as an insulator. i have just started using tapewounds on a recently assembled P bass, and am noticing the exact same problem. i've found that it's just something i'm going to have to live with.
peace
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That's what I was thinking too (the grounding issue).
Does putting a strip of scotch tape over the pickup poles affect the sound? Since it's a magnetic field, I'd think that it wouldn't. All I really need is a dot over the top pole, since that's near to where I rest my thumb on the top of the pickup.
Tapewound strings should not really cause problems with grounding by themselves. If the bass has a grounding problem, sometimes that can be exacerbated by using nylon tapewound strings, but it's not the strings that are at fault, it's the bass. And it should be easily fixable.
...Every time I touch a pole piece on the forward pickup (i.e. the one closer to the neck), I get a loud "zzzttt" coming through the amp. This was not the case with all-metal strings...
When you touch normal metal strings you ground your body but the tapewound strings are insulated.
tapewound strings cause buzz 
You're welcome to ask me computer questions in return!
