The start of Summer Singers’ 34th season begins today (Monday). New singers are welcome 7-9 p.m. Monday in Grant 114 of Norton Center for the Arts. This summer’s theme is “Musical Calendar” with music from eight different holidays, and includes several audience sing-along numbers, as is the tradition. There is no audition for this group, and all singers — new or experienced — are welcome. Those who can’t attend the first rehearsal but would still like to sing can email barbara.hall@centre.edu. There is a fee $45; for each additional immediate family member, $25 each; students in high school or college sing free.