The lyrics for the songs were not changed but Ilaiyaraaja composed new tunes for the songs that would be in sync with the already shot footage. The background music and the songs were recorded in Hungary's Budapest Symphony Orchestra and thus Hey Ram became the first Tamil film and the second Indian film to be re-recorded with a foreign symphony orchestra. The first one was Ilaiyaraaja's own score for the Malayalam film "Guru". The song "Isaiyil Thodangudhamma" was not present initially, but Ilaiyaraaja had seen an opportunity for a possible song in the scene and asked Kamal Haasan to give him a chance to add one. But Kamal Haasan, being the writer-director of the film, didn't see it. Then Ilaiyaraaja convinced Kamal Haasan to trust him with this and brought notable Hindustani singer Ajoy Chakrabarty to sing one of the most celebrated songs from the movie, "Isaiyil Thodanguthamma" and also writing the lyrics for the same.