The Mediaeval Baebes combine elements of Western European myth and folkloric tradition with linguistic fancy and overdone sensualism.

An example of the latter: in photos the octet will stand at the threshold of a leafy green forest, like an artisan's glistening porcelain figurines fashioned to please the provincial lord.

On the other hand they'll perform in haunting a cappella, singing in Middle English, archaic Latin and Italian, Cornish, or even Manx, a unique Gaelic dialect originally spoken on the Isle of Man in the Irish Sea.

So the Baebes are a study in contrasts, their work running fluidly between past and present.

Mirabilis continues that conversation, collecting folk ballads, pagan dance music, ancient love songs, and parcels of pure mystery.

Where some earlier albums emphasized synths and worldbeat textures too much -- whether as a crossover tactic or at the whim of a producer -- Mirabilis is happy with its zithers and recorders, finger cymbals and glockenspiels, and above all features voice.

When a keyboard does surface ("Kilmeny"), it's as a mood accompanist.

Opener "Star of the Sea" feels too much like a single, its Medieval English lilt too "period film" obvious.

But the Baebes are better with something like "San'c Fuy Bellha Ni Prezada," with its unadorned vocal and twining autoharp, or "Musa Venit Carmine," sung in Latin, in the round, and stippled with dynamic percussion.

These selections are exuberant, even catchy, but the mystery that lies in the heart of the Mediaeval Baebes' sound is never sacrificed.

"Märk Hur Vår Skugga" is even better.

A vocal trio harmonizes in an ancient Swedish tongue over the pluck of a zither and a violin's mournful sway; it's weird, cool, and beautiful.

The ethereal "Lhiannan Shee" is another highlight -- its layers of beckoning voices are like lures to a spirit world -- and "Cittern Segue" is a gentle interlude played on the titular instrument, a Renaissance relic which sort of sounds like a mandolin crossed with a harpsichord.