This video was created from the second movement of the 2014 piece ww8.
b2 is created by four voices which are set to trace out the four sides of a trapezoid in a slow upward glissando with no discernible tempo. Two voices gradually ascend, the other two rapidly. All four meet again at the octave. The four lines are at times close to one another and thus produce shifting beats which gradually dissipate as the voices become farther apart then other beats appear once the voices near and at last vanish at the point of the octave.
Please do not play this audio through laptop speakers, the frequencies are too low.