Max Reger’s music looks back as much as it does forward. The early 20th-century German composer’s Piano Concerto resounds with echoes of Brahms and Bach, but its extraordinary depth of texture and complexity of melodic line give it a startlingly modern edge. Markus Becker, an acclaimed champion of lesser-known repertoire, is a brilliant guide, opening up the concerto with playing of lightly worn virtuosity, the NDR Radio Philharmonic reveling in Reger’s rich, post-Romantic orchestrations. The accompanying piano miniatures are melodically and harmonically beautiful—on the evidence of these, Reger deserves a place among the modern era’s great piano writers. And the final “Choral” is simply magical.