This music is the Bourrée in E minor from the Lute Suite (also in E minor, BWV 996) by Johann Sebastian Bach. A Bourrée is a type of dance music and it is commonly included within Baroque Suites. This particular Bourrée was originally written for the Lute but on mfiles it is available both for Guitar Solo and Piano Solo. Since it is in two voices throughout, it is readily played as a Duet and the version on this page illustrates this using Oboe and Bassoon. Here are a range of alternative parts for different instruments, though some combinations may work better than others:
For this duet version illustrated on Oboe and Bassoon, you can play the mp3 file below or scroll down to see the sheet music score. Downloads of the PDF score, mp3 file and midi file are available via the links in the left-hand menu.