The latest album from bassist Stephan Crump of the Vijay Iyer trio, a new quartet project called Rhombal featuring saxist Ellery Eskelin, trumpeter Adam O’Farrill, and drummer Tyshawn Sorey, is very open, loose music with shifting tonalities and a nice tension between harmonic dissonance and steadily unspooling groove.

Crump has a bag full of ideas as a writer and reminds me of early much more avant garde Dave Holland records, say when Holland was with Anthony Braxton, the same sense of full tone and deft, cerebral, development always present in Crump’s playing.

The tunes in a sense are a series of innocuous miniatures but tend to expand into more than the sum of the parts, say in the steady unlayering of ‘Tschi’ or even delving way back into bebop gestures, eg on the swinging ‘Skippaningam’. Written for Crump's late brother Patrick there’s a lot going on here and above all terrific empathy between the sax player and trumpeter.

Crump has a gorgeous tone, great mobility and ideas, and can be very abstract as well as melodic. I hope this group manages to stay together and tour widely. They and the music here deserve the widest possible exposure.