I'm with guest on the question of this being an oxmoron.
Stan Hugil goes so far as to say how far off from authentic most recordings are. If it sounds pretty and musical, it is not being sung correctly! Loud, sharp and explosive is what a good shanty singer would have been. Not that I do not enjoy a pretty tune, and a cat screeching is not too entertaining, but the fact remains the"song" was meant to coordinate the work of a buch of people who probably were not art lovers, in a crowded, noisy and confused environment.
Speaking of Stan, have you ever heard him? YIPE! Authentic to be sure, interesting, yes, but only in the most masochistic way enjoyable.