Well, I think there are two sets of male singers in our country who are worth mentioning in any such review: -
(I) The LEGENDS
(II) The shadows of the legends(colloqually, ’copies’)
=(I) The LEGENDS: -
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10) Yesudas-(5/10)- Leave aside his diction and he seems to be the most organized singer. Very melodious, touchy and free-flowing tunes are what you associate with Yesudas. good singer!
9) K. L. Saigal-(5.5/10) - He is the forefather of Indian soulful music- the first superstar of Indian music Industry. His nasal tone may be irritating to many, but the generation when he sang demanded such a throw. take Shamshad Begum or Surraiya or Mukesh sahab or Noor Jahan or . all had this thing in common. It was the style quotient and Saigal Sahab used it the best.
8) Mahendra Kapoor-(5.5/10)- The best voice for patriotic and devotional songs. A synonym for Manoj Kumar. He was an underrated and underutilized singer. Many confuse his romantic songs with those of others but he remains an indelible chapter in Bollywoood music.
7) Jagjit Singh-(6/10)- The’Ghazal Samrat’, the’king of Philosophical renditions’. he needs no more description.
6) Talat Mahmood-(6.5/10) - The handsome hunk of yester-years, with an added advantage-’the silken voice’. sombre, lazy, magnetic songs: and you know that its Talat’s voice. the duets rendered by him are equally enchanting.
5) Hemant Kumar-(7/10) - If you need some sound sleep, get ten doses of Hemant’s songs as sleeping pills. so calming, so ethereal. more of a backwater. Great composer as well! I sometimes think that he would have been the nation’s best had the Bengali Film Industry not held him captive for so long.
4) Manna Dey-(7/10)- Classical guru! That’s the general idea about Manna Da. But he was as versatile as any other singer of his era. The only thing that did not earn him the deserved fame was that he always sang for the second-best actor in the Industry. otherwise- he could have sung anybody’s songs but nobody could have sung his ones.
3) Kishore Kumar-(7.5/10)- The mass’ favorite. the one who is most remembered till date. the most powerful voice to have graced the nation. one may just wonder where he would have been had he received academical music-training.
2) Mukesh-(8/10) - The undisputed champion of melancholic renditions. Raj Kapoor’s voice. I am seriously biased towards him. best timber, best throw, most ease. layman to expert- recognizable to all was his voice. I salute him!
1) Mohammad Rafi -(?/10)- too good to be rated:- He was, is and will remain the best. No second Rafi will be born. The vacuum created by his absence can be filled by none whatsoever.
=(II)The shadows of the legends(colloquially, ’copies’): -
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Sonu Nigam, Udit Narayan, Kumar Sanu, Shaan, Suresh Wadkar, Mohammad Aziz, Shankar Mahadevan, Bhupinder, Shabbir Kumar, Himesh Reshammiya, Daler Mehendi, Adnan Sami, Ravinder Jain, Subir Sen, etc etc.
There are a whole lot worth mentioning but the list above is just beyond comparison. These singers would themselves find it embarrassing to be clubbed together with the veterans of yesteryear.