by John Bush\r Where Tortoise-style indie rock and the Windy City's gradually more youthful jazz scene intersect lie Chicago Underground Duo -- also known as Chicago Underground Orchestra and Chicago Underground Trio with various lineups. The nominal leader, cornetist and keyboard player Rob Mazurek, recorded three albums for Hep from 1994 to 1997. As Chicago's own indie rock sensation Tortoise began leaning closer and closer to the city's improvisational and free jazz forbearers, Mazurek began playing with them and appeared on the group's 1998 album, TNT. The first Chicago Underground Duo album, recorded with drummer/vibraphonist Chad Taylor in 1998, appeared on Tortoise's Thrill Jockey label. The following year, the pair expanded to a trio with the addition of bassist Noel Kupersmith and released Possible Cube, on Delmark.