Remember in answering this question that you have stylists which most singers are, or you have technically good singers. A tech superior singer would be Mel Torme, also referred to as "The Velvet Fog" His pitch, tone, diction, and breath control were superior to most. Sinatra had no where near the technical skills possessed by Torme. Also the greatest male voices at jazz/pop have all been baritones. This is the one short fall of Mr. Torme, but at no time has Mr Torme been considered the greatest jazz vocalist on any poll I have encountered. That title has been suggested of people like Joe Williams. Any jazz poll would have to consider Louis Armstrong since he practically invented the jazz solo, and "scat" singing. Let us not forget the tech voices of Johnny Mathis and Billy Eckstine. In closing I distinguish between a technical voice and a stylist. Mel Torme wins hands down for technic, but Louis Armstrong wins hands down as a stylist.
