It is possible to create several polyrhythmic effects on the Double Bass.
These effects are possible through a certain number of technical permutations.
Some basic permutations are:
1) Different combinations of left and right hand pizzicato.
2) Hammer on's with both hands.
3) A sequence of fingered pitches with a different rhythmic arco articulation.
4) A combination of left/right hand pizzicato and hammer on's.
5) A combination of left pizzicato and arco/col legno techniques/percussive techniques
6) Hammer on's in one hand and arco/percussive/col legno technique in the other.
7) A sequence of fingered pitches with a different, rhythmic arco technique such as circular bowing (pulsed or unpulsed) and bow vibrato.
The polyrhythms can be of varying complexities but as the complexity increases, the polyrhythm can become more of a timbral multiphonic type effect will also emerge due to the variations in finger pressure when changing pitches.
Examples In Existing Works
Statements II - Barry Guy
Left & Right Hand Pizzicato
Trittico Per G.S - Brian Ferneyhough
1. Fingered pitches and conflicting arco rhythm on one string.
2. Fingered pitches and conflicting arco rhythm on alternating strings.
Anna - Barry Guy
Two hand hammer on's (unspecified rhythm)
Dialog Uber Feuer - Vinko Globokar
Two handed percussive effects on instrument body.