Quite right Jerry (though the thought of Johnny Collins singing "Everybody hurts" at shanty festival is a bit too much to bear...).

Johny Collins (and Jim Mageean too, with whom he sometimes duets) is a shanty (and other English trad) singer; sensitivity is not required in shanties, rhythm, pitch and volume are what he needs, and he's got that in spades.

Dave Bryant sings mainly music-hall ( at least the times I've seen him) and he is loud, but not at shanty-singing levels.

Graeme Knights straddle the area between the two (he does both shanties and music-hall, and he has quite a few reflective songs too). He can be very soft when needed, and he can turn it on when needed too, at scary levels.

Leadfingers is like Graeme in ability to vary volume. But he rarely does shanties, so I have never heard him at max volume, so to speak. He does have a piercing quality to his voice, which carries a distance (his experience of open air concerts, market fair singing etc must help him a lot there).

But the shantymen have it, for me, when it come to loudness. I would order the singers mentioned as follows, going up the scale: Leadfingers, Dave Bryant, Jim Mageean, Tom Lewis, Graeme Knights, Johnny Collins.