When doubled the quietly intense sound of acoustic guitar can approximate a small orchestra while still retaining the unique intimacy made possible by skin against string. In the right hands, such as those of the Assad brothers, the pairing can obviate all other sounds. Sent from their native Sao Paulo to study in Rio de Janeiro in the late 60s, the Assads have spectacular technique and worldly interpretive skills. To this they add an almost otherworldly musical empathy that places their performances on another plane, making them perhaps the finest guitar duo now performing classical music. Like many guitarists before them, inspired by the example of Andres Segovia, the Assads have opened their repertoire to the works of modern Latin American composers. But next to the expectable (Villa-Lobos) they offer such surprises as music by contemporary Brazilian composers–from the brilliant and elusive works of Egberto Gismonti to Sergio Assad’s own delicately spiced creations. This program, however, leans toward the traditional, with pieces by Rameau and Milhaud and a guitar reduction of Gershwin’s Rhapsody in Blue. Their appearance highlights the Sixth Annual Mid-America Guitar Ensemble Festival. Saturday, 7:30 PM, Pick-Staiger Concert Hall, Northwestern University, 1977 South Campus Dr., Evanston; 847-491-5441. NEIL TESSER

Art accompanying story in printed newspaper (not available in this archive): photo/Carl Friedman.