Hilary Hahn and Natalie Zhu prove they are an excellent duo team in their first recording together, featuring four of Mozart's sonatas for violin and piano. All dating from 1778 and later, Mozart treats the two instruments more equitably in these sonatas than in his earlier ones. Hahn and Zhu are technically flawless together. They match each other as closely as two different instruments can to achieve a true duet sound. Just as Hahn "digs" into her strings for extra friction in the opening of the Sonata in E minor, K. 304, Zhu aims for the same tone quality with her touch. The two use longer note values, enhanced by vibrato and pedal, to give the music a pretty sound. It's probably more than a Classical era purist would like, but this is by no means a Romantic interpretation. Their slow movements, particularly those of K. 376 and K. 526, have beautifully rounded, cantabile phrases. The Allegro con spirito of K. 301 has bright accents and intense diminuendos and crescendos, demonstrating that this music isn't all elegance and delicacy. What marks their performance overall is an infectious energy that draws the listener's attention. Hahn and Zhu have a lively spirit, but they balance it skillfully and knowledgeably with respect for the music, not taking it too seriously, but also not ignoring its significance as part of Mozart's oeuvre and as part of the violin and piano repertoire. It's a performance that is both well-informed and enjoyable, and makes the next effort by Hahn and Zhu something to look forward to.