Work for solo piano by Haydn performed by Sonia Chan on January 20, 2001 and work for string quartet by Haydn performed by Musicians from Marlboro on April 27, 2014.Haydn: Sonata in C minor, No. 33Haydn: String Quartet in B-flat Major, Op. 50, No. 1In the 1770’s and 80’s, Haydn found himself in a situation familiar to many artists: how to balance his day job with his budding career? Granted, Haydn’s day job was musical as well. He was the Kapellmeister, the musical leader, of the Esterházy musical establishment.But this steady gig came with strings attached: Haydn’s contract prohibited him from accepting commissions from any external source. The piano sonata written in 1771 demonstrates Haydn’s continuing musical growth. It was his very first piano piece to bear the “sonata” title, and it was longer and displayed more serious emotion than many of his earlier works.In 1779, Haydn renegotiated his contract to allow him to accept outside employment, and things began to change. His Opus 50, number 1 string quartet was among the fruits of this highly creative and productive period. The Opus 50 quartets were commissioned in 1784 by Haydn’s new publisher, though it took him a while to complete them. He finally delivered the manuscript to his publisher in 1787.