I can't say I could really listen to someone for hours - I'm a miserable old git who'll probably tell someone to belt up if they threaten to talk the length of a David Lean film - but there are certain actors/actresses voices that have certain appeal to them that can seduce the ear that much you probably wouldn't mind them reciting the telephone book.
An obvious one for me is John Hurt, that gravelly voice sounding as if it's had a year's supply of aggregate poured down it, yet compelling when the man uses it to great effect.
Another is Patrick McGoohan, a man whose voice managed to combine such tension and glacial majesty that I wondered if his vocal chords were at war with each other. A terrific, clipped, almost laser-sharp voice.
The ladies? I'd go for Katherine Hepburn's strident, energetic voice, a tone that slaps your face and shows you whose boss.
Any takers?