Kevin Micka (who performs as Animal Hospital) composes, produces, and performs his music alone, mining intense beauty from repeated patterns and heavy drones. In a live setting, he loops intricate moving parts to achieve the work of dozens. Except now Micka is expanding the band’s horizons, at least for two one-off performances. The Animal Hospital Ensemble (a group of over 30 musicians) will make its debut in Pawtucket tomorrow before arriving in Boston at the Pozen Center on Sunday.