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Ghantasala is the greatest singer the country has ever produced. All types of songs, padyams, slokams etc. have been sung by this great legend with a unique effect, which no other singer had did. Ghantasala possessed the most majestic and melodious and sharp voice which enveloped all other southern singers. K J Yesudas, spb were all there along with ghantasala, but not could stand before him in the south. Regarding rafi, there are similar numbers in hindi and telugu sung by rafi and ghantasala respectively for e.g. kuhu kuhu in suvarna sundari and chal ud ja re panchi etc. where ghantasala has a clear cut edge over rafi. Rafi cannot whatsover sing ragas similar to ghantasala, no doubt about it. so ghantasala is the greatest.