@slaw
I know what you mean all 3 kinda thin and breathy and can be something like ethereal. I think Beth’s voice is just a little more earthy than D’s. Meryum’s voice is more pure, like elemental vapor at times, and although this record of hers can put you in a trance, she might not be quite as talented as Beth. I don’t know about Dido - I think she benefited from machinery.