Billy Bang/Bill Cole : Billy Bang/Bill Cole

The didgeridoo doesn’t possess a very expansive melodic range, but when it comes to setting the mood with a rich drone, it does the job perfectly. The late Billy Bang’s violin joins Bill Cole’s expansive droning in this album’s opening improvisation, and they create a hypnotic sound, with long, bending tones and some vocalizations coming from Cole through his pedal point.

These six tracks, divided evenly between improvisations and compositions, come from a 2009 performance in Charlottesville, Va. An expert on Asian double-reed instruments, Cole plays different ones for the rest of the set, and, since none of the instruments are confined to strict Western pitches, each complements Bang’s expansive bowing. In “Shades of Kia Mia,” Cole’s nadaswaram sounds like a human voice singing in a haunting scale. The natural echo of the University of Virginia’s chapel makes the duo feel even larger. Bang sounds like two violins at one point during “Shades,” and almost like a variation on a trumpet during one of the improvisations.