Pickup Shielding

I have a Fender P bass. It originally came with a metal pick guard and sounded great. When I swapped the pick guard out with a plastic one, it added a low level hum noise. So, I attributed this to a difference in pickup shielding. My thoughts – it raised the noise floor and gave me less dynamic range.

I noticed that the cavities looked like they were painted with a black shielding type of paint. I shielded all the cavities and back side of the plastic pick guard with copper foil (better effective shielding). Afterwards, no hum at all. It sounded great, end of noise problem.

Question - If a bass does not have a pick guard to provide additional pickup shielding, will it have a higher noise floor and tend to have low level hum?

 

Thanks for the input.

The control and pickup cavities within the body are shielded with shielding paint. The top of the cavity is an issue as you pointed out. But I was wondering whether the noise was mainly being introduced from lack of shielding around the sides of the pickups.

I don’t own a G&L but I have heard that they have a low level noise hum. For a G&L, shielding the control cavity would be easy while shielding around the pickups wouldn’t (assuming the typical nice wood body with no pick guard).

I do have a Sting Ray and it doesn’t hum. I haven’t taken it apart though, so not sure what’s under the hood.

I will check out your search recommendation, thanks again.