Achu is the grandson of music director B. A. Chidambaranath who is considered to be one among the pioneers of Malayalam music industry. His father, Rajamani, was also a music director who scored for more than 1000 films in Tamil, Telugu, Kannada and Malayalam languages (He died suddenly in February 2016). He is a graduate from Loyola College, Chennai.
Hailing from a musical family, Achu's natural interest was to become a pilot. He chose music over aviation and became a full-fledged musician. He learned Carnatic classical from music director M. M. Keeravani.