Flatwound strings, or tapewound strings. Turn your tone knob off, back off the volume on your bass a teeny bit, and turn down the highs & high mids on your amp. Use your fingers or thumb on your plucking hand for playing and play at the base of where the neck meets the body. With your fretting hand, try to play RIGHT on top of the frets, instead of behind them.
SPECTOR® Club #369 | Fender Owner's Club #13