Not in objective terms, but a voice that really turns you on.
I pay particular attention to the quality and modulation of voice when it comes to acting. You can just listen to a voice and tell all the pain and experience that the personality must have gone through in life.
Not much aware of the recent actresses, but almost all the ones from few decades back, barring Madhuri Dikshit and to a little extent Raveena Tandon, have unappealing, shrill, shrieky, quaky, "fati baans", retarded, infantile, cringey voices.
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