Leo Chadburn – Primordial Pieces (self-released)   Composer and synthesizer performer Leo Chadburn uses very little in the way of material, but it is employed to craft expansive compositions. On “Reflecting Pool,” pianist Ben Smith plays repeated arpeggios with a sustained low note, shadowed by Chadburn’s bass synth. The unpredictable change of harmonies against the constant bottom note brings together a compositional conceit important to Chadburn, movement concurrent with stasis. Gradually, the synth bends the low note down, creating new chordal implications. A brief fade ends the work.    “Map of the World” is a piece for violin ensemble, played