Once we recognize the prolongation in a given piece of music, a harmonic progression becomes one unit – therefore, reducing the many notes to fewer meaningful objects that we can then relate to in a simpler manner.

Schenkerian Analysis posits that there are two main types of melodic lines: a 5-line and a 3-line. The two tasks that are before us today are to determine which one is used in this piece, and examine how this skeletal melodic line is being prolonged.

In this blog post, I will discuss the prolongation in the Bass line between measures 1-19 of Bach’s famous Prelude in C Major.