“It’s gonna be a party,” says jazz saxophonist Marcus Strickland of GroundUP, the eclectic festival that has lured like-minded music seekers from around the globe to the Miami Beach Bandshell since 2017. Its three days of performances, workshops and late-night jam sessions from Friday, Feb. 2 to Sunday, Feb. 4, are a chance to disconnect from the everyday and get fully plugged into the spirit of music.