The 40th-anniversary celebration at Nectar's continues with Jah9, billed as the "first lady of neo-roots-reggae." She'll perform at the venerable Burlington venue with guests Dubtonic Kru, plus selections played by Mi Yard DJs Big Dog and Jahson. The music starts at 9 p.m. Tuesday. $12 in advance, $15 day of show. 658-4771, www.liveatnectars.com.