These days sound engineers have become very crucial in music composing. Back Ground music mixing is not that easy. Till recent times the music directors used to mix the music with whatever machines they had.
AR Rahman had good modern machines and he used them for mixing and also the BGM. But now there are specified sound engineers who do their part in making music and also sound mixing apart from BGM.
That is the reason music directors like Rahman, Devi Sri Prasad and Thaman charge a bomb. There are sound engineers who charge lakhs for a film.
They are getting the credit during the titles in a film. Singers like Sid Sriram is charging 4 to 5 lakh per song and is in great demand. Sid has sung around 4 to 5 songs in Pushpa and his remuneration itself is around 20 lakh for the movie.
So it is justified if Devi Sri or Thaman is charging cores for the music. Even Ilaya Raj has constructed a new modern recording theatre and is depending on the mixing Engineers for some songs.
The tune is different the Sound is different and the mixing is altogether different. So don’t underestimate sound and music.