Now, I'm not referring to singing voices specifically. Though, you may choose people for their singing if you wish.
But, I'm curious MMO-C, whose voices are your favourites and why? Would it be the booming baritone of James Earl Jones in his roles as Darth Vader or Mufasa? Perhaps, it's Carrie Henn who played Newt in Aliens and mostly came out at night. Mostly. Or maybe it's Freddie Mercury and his powerful and flexible tenor? Hell. Maybe you're a narcissist and it's the sound of your own voice that you can't get enough of!
I'd say list 3, but up to 5 is cool too.
For me, it's:
Richard Burton - actor - His confident, Shakespearean delivery is the epitome of classiness (despite his decidedly proletarian beginnings). His voice feels like a smooth scotch.
Jennifer Hale - voice-actress - I first fell in love with Ms. Hale's voice when she portrayed Thorn, lead singer of the Hex Girls, in Scooby Doo! and The Witch's Ghost. She really did "cast a spell" on me. She is also Black Cat in the 90s Spider-Man cartoon, Commander Shepard of Mass Effect, Bastila Shan in KoToR and provides the voice for loads of other video game and cartoon characters.
Laura Bailey - voice-actress - Laura Bailey has voiced a wide range of characters. Kid Trunks in DBZ, Rise Kujikawa in the English Persona 4 dub and Jaina Proudmoore in Warcraft. She also voices Argent Confessor Paletress (dem crit wounded sounds). But, it's Laura Bailey's more melancholic and sultry performances that I go weak at the knees for. Lust in the English Fullmetal Alchemist dub and Serana in TESV: Skyrim, for example. I also love her as 'The Player' in the Saints Row franchise. She gives the character a really charming tomboyish, playful vibe that really compliments their lust for destructive sociopathy.