Chassidim were wont to say:
“What is the difference between a regular song and a Chassidic niggun?
A regular song expresses that the individual is in the mud and is joyfully frolicking in it.
However, a Chassidic niggun expresses that though the individual is in the mud, he is doing everything in his ability to escape.”[1]
[1] Otzar Pisgamei Chabad, Vol. 1, Pg. 388