Darama is from London, and Kush Arora comes from the Bay Area, but the two producers have a lot in common; namely, they both have a global ear for forward-thinking bass sounds, especially but not limited to music from London and South Asia. Rattle features three pan-geographical bass pumpers. It might be easier to list the subgenres not explored in these tunes. On the title track, a bhangra-informed lead line dances with London-meets-Durban polyrhythms—flutes twinkle and bass wobbles. “Grid” rocks with a tough fusion of grime pressure and a double flute melody; “Heart Meter” skips along in a tough style.