do pots change the vol of sound

Hello, somewhat new to modding. I usually just buy a good bass IMO.
I just got my second HB the PJ5-SBK deluxe, and changed it to all black.
The OG J pickup was super noisy to where it sounded like an AC behind a closed door. So I bought these :Wilkinson 5 Strings PB electric bass Guitar Pickup Five strings P bass Humbucker pickups WOPB5+WOJB5. The sound it a bit low like I need about 3 more turns to get the vol up. The pickup and pickguard were the only change. Do I need to change the pots or maybe it is something else???? any help would be great. It looks like the one on the right but black everything.