Traditional music in Guinea, Mali, Senegal is more nostalgic and sad than in Nigeria, Benin and Ghana. One of the reason might be the still strong influence of the fallen Malian empire and also I think that the traditional string instruments, the Kora and the N'goni, make a big difference and open the doors of deeper melodies. As an example I present you with two differents versions of "M'borin" where sadness triumphs over joy.
1977
Camayenne Sofa: "M'borin"
1996
Africando: "M'borin"