Gwenno Saunders has just turned out the best Cornish language album of this or, let’s face it, any decade, Le Kov. True, there’s no competition, but a fine piece of work it is in its own right, combining a mysticism that’s familiar from the well-established Welsh language scene with floaty electronics not dissimilar to a previous Hidden Door visitor, Jane Weaver.

Tonight’s forty minute set is a fairly faithful recreation of that sound, with little deviation or expansion on the recorded output. It’s an early test for the Hidden Door sound system though, the bass rattling roughly and distorting, a problem that’s later resolved. No such trouble for Saunders or her fellow female keyboardist whose electronics and vocals come through sharply.

Those English monoglots who’ve listened to Le Kov oblivious to the meaning of the lyrics might be deflated to find they’re not about mind expansion or space or faerie folk or whatever the musical atmosphere and your condemnable preconceptions about Celtic language might lead you to believe. Eus Keus?, for instance, is about cheese, or at least an ancient cheese-based saying. (If “best Cornish album of the decade” sounds like faint praise, Saunders tells us we’re the largest congregation of Cornish-language chanting people in Edinburgh history. Quick, someone call Norris McWhirter!)

The same is true of her Welsh Music Prize winning debut Y Dydd Olaf. As far as it’s possible to tell, the lyrical content is more general purpose than you’d imagine. “This is about how shit the patriarchy is,” is how she introduces her second song, Patriarchaeth, with all the perspicacity of a late 60s hippy telling you, “war’s a real bummer, man!”

“Darkness is another kind of light that reveals true beauty,” is the aphorism that forms the basis of another song, and for a second we’re into what seems more spiritual territory. “It’s from a hymn. I’m not being religious though!” she says, like that would be the worst thing in the world. “It’s about art.”

Which seems to be the measure of Saunders. With her tambourine shaking and the vaguely educational way she introduces each song, she’s your funky art teacher doing a musical side project, painting pretty aural kaleidoscopes for your ears. This isn’t soul-deep, mind-penetrating or libido-stirring stuff. It’s airier than that. The contrast with the more primal Nadine Shah who follows her as headliner is striking.

Airy is not necessarily a bad thing of course. Single Tir Ha Mor is lovely, and the first levelling up of this year’s Hidden Door. But while it might at first glance have seemed perplexing that Gwenno was so low down the bill, it’s easier to understand afterwards. It’s a playback of some nice tunes you may have heard on the radio, not a barnstorming live performance.