Email the bands and ask them.
EDIT: After listening to the Poogie Bell stuff...
I would suggest boosting the lows on your EQ... a lot. If you can, also boost the high mids a bit to keep the definition. Cut the treble. Some sort of slight overdrive from a pedal might help get some growl. Using 10" speakers would help, in my opinion... though I realize that means spending money.
Also, use a P bass.
