Violinist Andrew Manze and harpsichordist Richard Egarr take a sonata by Arcangelo Corelli into new territory — at least for modern audiences. Manze improvises within Corelli's score, as he believes was common practice when it was performed in 1700. Manze and Eggar's new CD is called Corelli Violin Sonatas, Op. 5. Hear NPR's Melissa Block and NPR's Fred Child.