Hwang and Duval collaborate once again in The C.T. String Quartet, an exceptionally exciting improvisatory group named after Cecil Taylor, with whom Duval enjoyed a fruitful association. Along with cellist Tomas Ulrich and violist Ron Lawrence, the Quartet explores the full range of the strings with an unflinching intensity and an uncommon emotional depth. Under the Pyramid is only the Quartet’s second album, the first being the equally masterful The Navigator (Leo). In the liners, Duval describes the music as “shades of dark,” which, although true, tells only part of the story. The dense undercurrent dazzles with dizzying severity, and the tenebrous colors provide satisfying depth.