Tommy Dardar was a linchpin of Houston’s blues scene, a soulful singer, world-class harmonica player and overall down-to-earth cat who lately could be found performing his roadhouse R&B with a New Orleans twist at local joints like Shakespeare Pub, re:HAB and The Big Easy. Dardar passed away last month at age 66 after steadily making music in Houston for 40 years; he sat in with Lightnin’ Hopkins as a young man, and in later decades fronted two of the city’s more popular rootsy combos, Soul Bros. Inc and Big Daddy Gumbeaux & the Big Easy Rhythm Rockers. In that time he also built up a wealth of friends, many of whom will be on hand for Sunday afternoon’s tribute show organized by James Nagel, a.k.a. the “Blueshound” co-host of KPFT’s Howlin' the Blues. Scheduled to appear are Evelyn Rubio, Allison Fisher, Tommie Lee Bradley and many more, plus — in a final salute to Dardar’s affinity for all things Big Easy — a special second-line celebration that will spill out into the streets of West U.