The Splitz could have been the second Milwaukee band on Slash Records after Violent Femmes. John Jaco and his bandmates declined the label’s offer in 1990, and an indie debut album followed two years later. Mortality Curve follows more than a quarter-century later as if extricated from a stylistic time warp few acts have visited. Jaco’s warmly arch vocals and melodies address personal and societal moral concerns with a sound conflating dual Midwestern rock traditions: the pop prog of Styx and Kansas and power pop recalling Off Broadway and Spooner. It’s a curious amalgam but with a larger potential listenership than they may think.