There’s likely no better example of chamber-pop music in Louisiana than Baton Rouge’s Minos the Saint. For the band’s second album, Atchafalaya Child, Peter Simon’s earnest yet playful songs are dressed in elaborate arrangements crafted by the band’s multi-instrumentalist polymath, Ben Herrington.

A large band, Minos the Saint’s Atchafalaya Child instruments include trombone, trumpet, mandolin, saxophones, violin and Herrington’s keyboards. Lavishly produced, the songs also feature multiple sections and tempo changes plus ambient epilogues that, in the case of “Menorca,” extends the song to more than 10 minutes long.

The old prog-rock label doesn’t do Minos the Saint justice. Because the band is so successful in manifesting its expansive vision, it defies conventional categories. Brass-heavy arrangements suggest that famous pop-jazz horn band, Chicago, as well as “Sgt. Pepper”-era Beatles. All the while, Atchafalaya Child, despite some meandering ambient sections, is accessible and beautifully performed.

Only Minos the Saint’s second album in 13 years, Atchafalaya Child rewards with 13 meticulously executed tracks running for more than an hour. “When the Master Calls,” for instance, sets the project’s prog-classical chamber music-pop-jazz scene with “Sgt. Pepper” and Chicago flourishes plus a solo by jazz saxophonist Brad Walker.

Another of the album’s intricately arranged songs, “Madness or Method,” contains Celtic music flavor plus the waltz tempo that’s repeated in the album’s quietest and least orchestrated song, “Time to Be Happy.” The group’s instrumental palette expands again when ethereal pedal steel guitar complements Simon’s wistful lyrics for the title track “Atchafalaya Child.”

A sonic voyage, Atchafalaya Child ends with “Shiny Things,” a large ensemble piece with poignant, anthem-like resonance. All of the above reveal that Minos the Saint is among Louisiana’s most musically ambitious and technically accomplished bands.