This paper offers a new explanation for the barytone and oxytone accents attested for the Vedic - ti-stems. The two accents are commonly taken to derive from separate reflexes of a once unified proterokinetic paradigm, and it is against this account I will propose the divergence is instead chronological: oxytones belong to the oldest layer of the Vedas, barytones to the younger. The diachronic change we observe occurs within the Vedic period, and is localized to the accentual properties associated with the suffix - ti-. Our philological analysis of the - ti-stems across Vedic texts will support the “compositional approach” championed recently by Kiparsky (2010) and Kümmel (2014) against previous approaches. Finally, I will suggest answers to the question of how the accentual properties of - ti- changed based on recent research into the lexical phonology of accent systems.