Assuming that this was a serious question, (no doubt I'm wrong once again), I think its a great question. To me, voices are very personal choices. Harry Chapin, for example didn't have a melodic voice at all, but he could inspire tears in Corey's Comin'. The Duet of Sarah Brightman and Andre Bochelli is beyond the pale. At the totally personal level, I love a 50 year old voice of Joanie Sommers singing 'Once' with Laurindo Alemedia. (spelling??)
I do know this the right singer, male or female takes music lovers into a different dimension.
Love the Question.