Town Hall. 8pm; $25, $35, $45. Ladysmith's soothing a cappella style has become so recognizable that it's beginning to show up on TV commercials. If you've seen the South African vocal troupe, you know how well traveled their vocal acuity and tiptoeing dance moves are. If you haven't, there's no time like the present. South African singer-songwriter Vusi Mahlasela opens; find out why he is considered a national treasure in his home country.