In phase-based syntax, syntactic structure is sent in chunks – spell-out domain by spell-out domain – for phonological interpretation. The spell-out domain of an embedded clause would, then, form a separate phonological domain from its matrix. In this paper, I test this theory on the prosodic phrasing of relative clauses in some Bantu languages, and show that the phrasing contradicts the proposal that embedded spell-out domains necessarily form distinct prosodic domains. Instead, the phrasing is most consistent with a non-cyclic Edge-based analysis, in which only one edge of a syntactic phase constituent is aligned with the edge of a prosodic phrase.