‘I’ll leave you with the cosmos,” Australian singer Kathryn McKee – or K Mak – whispers dreamily at the start of this ethereal but oddly muted gig. A globe of light emerges and vaguely spacey projections beam around the band as their electro-classical orchestration soars into life. From there, with no other interaction with the audience, the show struggles to gain much velocity.

Freeze any moment of this performance and the snippet of synth-infused symphony you catch will have an otherworldly beauty. But in the room, with the band squashed awkwardly against the back wall so as to be caught in the projection’s light, the energy is halting. The action feels untethered from the space we occupy together, neither party quite sure what to expect from or offer the other.

The instruments are an easy extension of their players, the irrefutably accomplished musicians on drums, violin and cello sometimes closing their eyes as they lose themselves in the mournful music. The voice of K Mak, who is also on keys, comes to us first with heavy synths, her voice high and alien, her lyrics taking effort to unpick. Then she strips back the modulations to give us her voice unfiltered, her just-discernible words of love and longing making it equally possible that she’s speaking as a person as she is a star.

Behind the performers, psychedelic projections veer from micro to macro, from abstract and tangible, with globular molecules and rushing comets colliding as if tilted through a kaleidoscope. These trippy visuals have the most impact when they feel tailored to the music, a burning flame around a black hole pulsating in time with the beat of a drum. But moving on to images of bouncing jellyfish and unfurling flowers, they begin to seem compiled at random. Losing any connection to outer space, they threaten to tip into the abstract bounce of a desktop screensaver. The music may be cosmically calming, but this performance lacks the intensity required to either truly ground or transport you.

• At Summerhall, Edinburgh, until 24 August

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