I haven't found much information on this album. It was released in 1976 by D.G.A.C. (Direction Generale des Affaires Culturelles du Congo - General Administration of Congolese Cultural Affairs, Congo-Brazzaville). It's a celebration of the national musical talent, enlisted to uplift Congo' scientific socialism of the time. For French-speakers, there's Vision, a lament about slavery's chains, imperialist orders, and popular revolutions.
Congolese coups, assasinations, and revolutions aside (Congo-Brazza saw its share of those), this album showcases the talents of master musicians like Essous, Pandi, Malapet, Ricky Malonga, and Passy Mermans. At that time, 1976, they already had a long history behind them in bands like Bantous de la Capitale and Rock-A-Mambo (as well given serious infusions to Franco's OK Jazz), and here the musicians sound like they're having fun with musical experiments, a revolutionary version of Tokumisa Congo (We congratulate Congo) in Ah Congo! and straight classic grooves like Pembe Kanisa.
It's a great album. I never heard or saw a Volume 2...
Orchestre National du Congo - Ntima Ngongo
Orchestre National du Congo - Pembe Kanisa
Orchestre National du Congo - Kintuari
Orchestre National du Congo - Ah Congo!
Orchestre National du Congo - Vision