New Pickups HOW AND WICH

[I<3Bass]

First HOW do they change the sound of the bass?

Wich should i get for a pbass I don't want too much low or too much high just right in the middle.

[Tryxx]

Pick-ups simply sound different because of what they're made out of, how they're coiled and several other things.

Here's a thread on talkbass reviewing several P pups from different manufacturers.
http://www.talkbass.com/forum/showthread.php?t=127322