Mumbai, May 30 (IANS): Singing legend Asha Bhosle is set to join Anu Malek, Sunidhi Chauhan and Salim Merchant as the fourth judge on the sixth season of popular singing reality show "Indian Idol".

"The first thing I will ever look for in any contestant is their sur. My focus will be on sur because it is the most important part of singing. I don't like singers, who are not been trained properly," Bhosle told reporters here Tuesday.

"It is very important for singers to have a classical training as it helps them to sing the right notes. If the foundation of a building is strong, it stands tall forever, similarly, classical training sets the base for good singing," she added.

Bhosle, who is known for legendary songs like "Ek pardesi", "Piya tu ab to aaja" and "Yeh mera dil" has earlier been a part of several reality shows but as a celebrity judge, while "Indian Idol 6" will see her taking her a full-fledged role as a judge of the show.

It was earlier reported that music maestro A.R. Rahman was also approached for the show but things didn't work out. "Indian Idol 6" is set to go on air June 1 on Sony channel.