I love birds. Since I was a child I always had a very special feeling in my heart for any aviary being. I will never forget the deep emotion of love, beauty, sacrifice and tenderness I felt the first time I attended an exhibition of Sri Chinmoy's soul-birds.
While searching for sound samples with a proper license to use for some of our Radio programs, I discovered this beautiful recording of a Nightingale's song:
http://freesound.iua.upf.edu/samplesViewSingle.php?id=17185
The web site at http://freesound.iua.upf.edu is filled with other beautiful sounds. For example, listen to this bowl struck:
http://freesound.iua.upf.edu/samplesViewSingle.php?id=2166
Highly recommended!