Ilaiyaraaja was one of the early Indian film composers to use Western classical
music harmonies and string arrangements in Indian film music. This allowed him
to craft a rich tapestry of sounds for films, and his themes and background
score gained notice and appreciation amongst Indian film audiences. The range of
expressive possibilities in Indian film music was broadened by Ilaiyaraaja's
methodical approach to arranging, recording technique, and his drawing of ideas
from a diversity of musical styles.
According to musicologist P. Greene, Ilaiyaraaja's "deep understanding of so
many different styles of music allowed him to create syncretism pieces of music
combining very different musical idioms in unified, coherent musical
statements". Ilaiyaraaja has composed Indian film songs that amalgamated
elements of genres such as pop, acoustic guitar-propelled Western folk, jazz,
rock and roll, dance music, psychedelic, funk, doo-wop, march, boss nova,
flamenco, pathos, Indian folk/traditional, Afro-tribal, and Indian classical.