Originally formed two decades ago while students together at Indiana University, Straight No Chaser has reassembled and re­emerged as a phenomenon ­ with a massive fan base, more than 80 million views on YouTube and proven success with holiday releases. If the phrase “male a cappella group” conjures up an image of students in blue blazers, ties, and khakis singing traditional college songs on ivied campuses… think again. Straight No Chaser (SNC) are neither strait-laced nor straight-faced, but neither are they vaudeville-style kitsch. See for yourself when their 20th Anniversary “I’ll Have Another” world tour plays the Long Center.