I propose a listening of Riccardo Stracciari singing "Cortigiani, vil razza dannata" from Rigoletto.
Warm, fabulous legato, great depth and a wonderful combination of brightness and darkness
Riccardo Stracciari Sings "Cortigiani, vil razza dannata, " From Rigoletto 1927
http://www.youtube.com/watch?v=T0Ycs6-I0pI