All Music Guide:
Fourth World, Vol. 1: Possible Musics starts off from the same basic idea as Hassell's previous solo albums: a blend of avant-garde composition, jazz soloing, and African and Middle Eastern rhythmic forms. This album adds Eno's characteristic production touches, like the reversed echo that gives a ghostly, unreal edge to Hassell's trumpet solos on the side-long "Charm (Over Burundi Cloud)," African hand drummers on the hypnotic "Delta Rain Dream", and most crucially of all, the great percussionists Naná Vasconcelos, from Brazil, and Aiyb Dieng, from Senegal.
