If Celtic Connections celebrates Caledonian music's global network, so too does it engage in time-travel.

It traces historic musical roots while bearing contemporary fruits, as evinced by this endearing alliance from Glasgow folk-rock alchemists Trembling Bells and their 60s psychedelic forebear, Mike Heron of the Incredible String Band.

Having played occasional live dates together since 2011, Trembling Bells and Heron's first fully collaborative outing made for a magical, convincing match: they reanimated some of Heron's best-loved ISB incantations – Cousin Caterpillar; A Very Cellular Song – and Trembling Bells's mercurial vocalist Lavinia Blackwall even commanded a startling rendition of Waltz Of The New Moon, composed by ISB co-founder Robin Williamson.

That Heron also covered the Carbeth-era Trembling Bells is testament to the vintage, impeccable song-craft of TB frontman Alex Neilson (he largely played on drums): one of the evening's biggest cheers came with the incandescent acid-folk climax of I Took To You (Like Christ To Wood). The stripped-back moments were particularly moving: Heron's a cappella duet with daughter Georgia Seddon on Bright Morning Stars; the era-straddling, mystic thrill when Heron's band and Trembling Bells sang Douglas Traherne Harding, unaccompanied, together – "One light ... crowned with stars" – and so it was.

HHHH