This special edition of “Sing Out” features a live performances by young rock band Dear Indugu, and jazz duets by pianist Peter Apfelbaum and percussionist Josh Jones, representing the once-only reunion of more than three dozen players from three generations of Berkeley High Jazz Ensemble alumni on Sunday, March 15, at King Middle School. Apfelbaum and Jones were charter members of the Berkeley Schools music program and founders of Hieroglyphics Ensemble 30 years ago.