The Bach/Gounod Ave Maria is a popular and
much-recorded setting of the Latin text Ave Maria.
Written by French Romantic composer Charles Gounod in
1859, his Ave Maria consists of a melody superimposed
over the Prelude No. 1 in C major from Book I of the
Well-Tempered Clavier (BWV 846), composed by J. S. Bach
some 137 years earlier. (Gounod adds one bar so as to
smooth out a rough change in harmony in the prelude.)
Wikipedia
The pan flute, also known as the syrinx, is an ancient musical instrument made up of multiple tubes of different lengths aligned side by side. This instrument belongs to the woodwind family and produces sound when the player blows across the opening of each tube.