‘Last Leaf’ refers to the last leaf of parchment in the Codex Runicus, a tome dating from around 1300 that contains one of the earliest pieces of Nordic legislation but also, on that final page, the secular song ‘Drømte mig en drøm’ (‘Dreamed me a dream’). This album is arranged as a sort of codex in itself: a heartfelt, thoroughly researched and exquisitely performed journey through that and other Nordic folk songs, dances and hymns from the past five centuries that ends with the single piece that inspired it.

That piece, ‘one of the most beautiful Danish hymns we know of’, according to the Danish Quartet, is ‘Now Found is the Fairest of Roses’, in which the theologian HA Brorson laid his yuletide text over a Lutheran funeral chorale. It is played here with the combination of focused lightness and floating tension that the DSQ might deploy in a Beethoven slow movement. In the end, it slips away – the most saddening but smile-inducing moment in an album that traverses simple emotions but taps something deep at the same time.

Indeed, the quartet pose a parallel question in the booklet: ‘Can a rustic folk dance conjure up feelings of melancholy and contemplation?’ The ensemble’s considered arrangements provide an answer as much as their performances. Repetition presents an opportunity to layer, weave, darken and question. Never do any of the arrangements drift into the schmaltzy (we hear a double bass, a harmonium, a piano and a glockenspiel in addition to the four strings of the ensemble). When presented with unusual material, as in the arrangements the ensemble has discovered by the 18th-century Danish fiddler Rasmus Storm, the performances mine its unusual qualities. There are three original works by cellist Frederik Sjölin, the best of them Naja’s Waltz, which moves from a light pizzicato to a deep-throated song.

‘In the old days’, continues the quartet’s own booklet note, ‘you were considered a good fiddler if you knew a lot of tunes, you could play loudly for a very long time and most importantly, you kept the beat.’ They certainly do the latter. But they also invest this music with the sort of ensemble precision, subtlety of colour and well-timed abandon that they do Shostakovich and the rest of them. The best album of folk ditties from a string quartet you’ll ever hear? Probably.