The Bartók disc, assembled from concerts in Freiburg, starts with a snapshot of the composer freeing himself from Debussy and Strauss. The constant presence in the Four Pieces (almost to the point of direct quotation) of moods and effects from Duke Bluebeard’s Castle and The Wooden Prince makes the score a kind of symphonic epilogue to those two stage works. Gielen rightly strikes the balance between Romantic and modern, never denying the music its textural weight but not losing the anarchic contrasts of rhythm and colour that Bartók derived from his folk-music researches: a first-rate reading of a too little known score.

The unfinished two-movement First Violin Concerto, an abortive declaration of love for the young Hungarian virtuoso Stefi Geyer, is even more of a mêlée of old and new: the soloist is rarely silent and the accompaniment attempts to stay primitively rhythmic but fights a losing battle with more pictorial excursions. Christian Ostertag and Gielen give it with a passion and edge matching Bartók’s description of it as a portrait of both the personal and professional characters of his would-be muse.

Sourced from two performances, Gielen’s handling of the 1936/37 Music for Strings, Percussion and Celesta has an improvisatory feel. He seeks drama and expressionist colour rather than letting (as Boulez does) the precise mechanics of the scoring and the ensemble do the piece’s work for him. If Fricsay’s manic, ethnic energy, Reiner’s tautness and colours and the Sony Boulez’s super-precision are not displaced here, Gielen’s is a strong contemporary view, worth hearing in the novel context of the disc’s earlier Bartók.

The Brahms coupling (a radio studio recording and the first of a symphonic cycle from these artists) is deceptive. At first it seems Gielen is merely essaying an unobjectionably non-romantic play-through but a second hearing reveals an altogether exceptional grasp of the line and argument of the symphony, allied to (and this is especially noticeable in the Tragic Overture) a precise observation of Brahms’s far from conventional rhythmic structures and scoring. Clearly if you believe the timpani in the symphony represent ‘der deutsche Herzschlag’, and seek the almost catatonic crisis that Furtwängler finds in the slow opening of the finale, this should not be your first port of call. But if you want a leaner, brisker Brahms without recourse to original instruments, this is intelligent and enjoyable. Gielen’s Third and Fourth Symphonies should prove intriguing.

SWR’s recordings are true, lifelike (although the layout of the orchestra in the Bartók Music is not so clear) and not especially warm. Their notes are original and excellent.