One of my favorite techniques for Hip Hop is the octave. It's a great tool to set a strong accent. I like doing this with my five string, playing the low octave on the B. The example below should be played a string lower than displayed, but the line builder has (many) limitations. The octave chords are on the E and G in bar 1 and on the F# in bar 2.
Another concept to spice up Hip Hop grooves is playing staccato. Silence is very important to outline a rhythm. Pay close attention to the lenght of the notes.
The D to E in bar 1 (open D string to 2nd fret) should be played as a hammer-on. I sometimes play the last note D on the A string, using slight vibrato for the last notes B and D.
The ideal instrument for Hip Hop basslines is the upright bass. The warmth of an acoustic instrument, along with the extra depth of the upright bass, is great for a cool low groove.
