im 99% sure that bassline in "pick it up" was filtered out from a sample, what i do for nice CLEAN ass bass is take a baseline from a sample, put it into a sound editor, zoom in on the waveform, and take out that peice that is one complete waveform pattern. kinda hard to explain hold on ill post a picture
edit:
theres a pic of it, then i switch on something called CRF (crossfade loop) and it makes it loop and hold a note
i eq that shit and in the words of emeril, BAM!
note the up down bumps on there, just take out like 1 up bump and one down bump and its just like raw bass
or i just eq some jammin ass bass soundfonts or something, i take out all the highs and most of the mids sometimes all the mids and it sounds real smooth