A traveling trumpet player returns to his native Iowa this week after nearly two years on the road. 25-year-old Adam Robertson, of Cedar Rapids, is a cast member in the show “Blast!” which opens tonight (Tuesday) in Des Moines. Robertson says it’s hard to describe what the production is all about — outside of being high-intensity music and marching. “Blast!” was created by Iowa native and U-N-I grad James Mason, who co-founded the champion marching band “Star of Indiana,” then put on “Blast!” in New York City, winning a Tony Award and an Emmy in 2001. Robertson, a University of Iowa grad, says “Blast!” is a production that stimulates the senses of sight and hearing.Robertson’s been touring the U-S with “Blast!” since April and was on the cast of “Shockwave!” for a year before that. This current tour wraps up next month so Robertson says it’s about time he starts looking for work again. The cast of “Blast!” consists of 54 members, most of whom are in their 20s, blowing bugles, tossing flags and thumping drums. “Blast!” runs nightly tonight (Tuesday) and Wednesday and twice daily on Friday through Sunday at the Civic Center of Greater Des Moines.