Before becoming principal conductor of the Danish National Symphony Orchestra in 2017, the Italian Fabio Luisi knew little of Carl Nielsen’s music. This outstanding coupling of the composer’s First and Third Symphonies, released five years later, shows Luisi was a rapid learner. His view of Nielsen is lithe and athletic, the opening movement of Symphony No. 3 bristling with vim and vitality. By contrast, Symphony No. 1’s slow movement is richly nuanced and expressive, Luisi unfailingly locating tempos that allow the structural outlines to unfurl organically. The Danish orchestra plays its native composer with a trenchant sense of idiom and assurance, making a powerful case for music that is still widely underappreciated.