Trans-Siberian Orchestra

When the Trans-Siberian Orchestra debuted their symphonic take on Christmas music in the late-'90s, it sounded an awful lot like a novelty. In the years since, however, their progged-out, light-show-assisted tours have become an enduring traditionnot to mention a lucrative one. The group's recent tours have been raking in about $40 million a year, as the band has proved so popular that its split into two touring groups to further capitalize on the seasonal demand. Next summer promises to see the release of the outfit’s fifth albumand their first not themed around the holidaysNightcastle, but for now the group doubles down with a pair of shows at the Bradley Center today, at 3 and 7:30 p.m.