Pride of place on the third volume in Leif Segerstam’s Turku PO series for Naxos of lesser-known Sibelius goes to the incidental music that the composer provided for a 1905 production in Helsinki’s Swedish Theatre of Maurice Maeterlinck’s symbolist drama Pelléas et Mélisande. Sibelius salvaged all but one number for the orchestral suite – go to track 9 to hear the dusky three-minute sequence containing some imaginative writing for principal cello that he left out – and of course we also get to hear Mélisande’s haunting Act 3 song ‘The Three Blind Sisters’ in its original vocal guise (soprano Pia Pajala sings it most eloquently, too). Segerstam masterminds a pungently characterised and keenly perceptive rendering. His daringly spacious treatment of the concluding Andante (entitled ‘Death of Mélisande’ in the suite) tops the seven-minute mark, but so sure is his control of line it never drags.

Next comes the unpublished and often appealing Musik zu einer Szene, dating from 1904 and originally designed to accompany a tableau. All but one of the four remaining items – namely the charming pastoral miniature Autrefois of 1919 with its fetching vocalise for two voices– are waltzes: the manuscript of the innocuous Morceau romantique (1925) was auctioned to raise money for a children’s hospital, but the less said about the feeble Valse chevaleresque (1921) the better.

The lion’s share of Vol 4 is given over to what is only the second complete recording of the extensive score that Sibelius supplied for the Finnish National Theatre’s November 1916 staging of Hugo von Hofmannsthal’s Jedermann, anadaptation of the medieval morality play Everyman. This dates from the period when the composer was immersed in the second version of his Fifth Symphony and was a venture that incontestably ignited his imagination – just sample the searchingly inspired string-writing in Nos 11 and 14, the commodious skip of No 4 (‘Dance Song’) and No 8 (‘Oi, Lempi, armas Lempi!’), or the stoically affirmative angels’ chorus which closes proceedings. Throughout, Sibelius employs his varied vocal, choral and instrumental forces (including piano and organ) with striking resourcefulness. Segerstam’s often daringly spacious conception absorbingly complements Vänskä’s splendid Lahti account – diehard Sibelians will, I fancy, want to have both – while Turku PO member Mikaela Palmu responds with big-hearted dedication in the lovely Two Serious Melodies for violin and orchestra (1914 15). Alas, to my ears at any rate, Segerstam’s waywardly measured view of the glowering 1910 tone-poem In memoriam doesn’t come off, but everything else on this finely engineered disc most certainly does.