There is a sense here of how long and far Simon Rattle has journeyed with this music – one of his very first recordings (famously so) was of the Fifth Symphony – and by the time we reach the Seventh and last symphony it is indeed almost tangible. I’m not sure I can remember the opening bars of that piece feeling quite so remote, evolving rather than beginning, emerging unformed from the substrata of what has gone before. In that, the famed Berlin Philharmonic string basses – sunk too deep to fathom – are the organic foundation of these performances: the point from which the sound begins and ends.

But that sound – big-boned, fleshy, well-upholstered – is also a bone of contention for me, a handicap in some respects. Thinking back to before Rattle was Sir Simon, when part of his bonding with the City of Birmingham Symphony Orchestra came out of that first Sibelius cycle, I am mindful, listening to the new one, of just how important the angular, edgier, rhythmic aspects of this music are to its evolution and how easily they can be compromised by a surfeit of ‘tone’. The beauty of this music is born of a more primitive hue. So, Karajan’s legacy notwithstanding, and for all the fabulousness of some of the playing, I am not entirely convinced, and never have been, that this is the right fit of orchestra and music.

Indeed, if you listen to the cycle chronologically, the first three symphonies are conspicuously disappointing in this respect. You could argue that the First – the most Tchaikovskian of the canon – revels in the Romantic amplitude of the music. It is quite an earful in the outer movements, the big sorrowful tune of the finale darkly resplendent. But the Berlin Philharmonic are inclined to ‘shapeliness’ in all things; and that, coupled with the fleshiest woodwind sound in the business, means that even the desolate clarinet of the opening sounds too knowing of its pedigree.

In the Second, too, one is too conscious of the ‘blend’ making for thickness, particularly in the inner voices. The rhythmic elements often feel compromised here, the spread of the sound inappropriate with even the timpani muddied at the rear of the orchestra. The speed of reflexes, the sharpness of articulation, are not always what you want them to be, and it’s hard moving this big, plushy sound across so very particular a terrain. Rattle almost pulls off a really impulsive accelerando through the stormiest transition of the finale into the second appearance of the big tune, but it is sheer willpower and the force of his personality that pushes against what one feels is an inherent resistance.

The Third, of course, is almost entirely about concision, rhythm, movement – and though there is nothing wrong with the tempi per se in the opening movement (too many, including Barbirolli, take it too slowly), the sense of the imperative that makes the outer movements so exciting is missing. The economy of means needs to be reflected in the leanness of the sound. And, beautiful though it is, I am not thinking cool and refreshing but rather warm and consoling in the second movement. That said, Rattle does catch the mysterious light of solo strings at the heart of it.

The last four symphonies fare markedly better, with the Fourth undoubtedly the star turn of the cycle. From that dramatic plunge into the unknown – a bleak, almost alien landscape with lowering basses – the expansive (expensive) Berliners at last sound at one with the epic spareness of a piece with two slow movements, and Rattle ensures that space is seemingly created in the playing of them. We are fathoming the unfathomable; and in the great second movement (with Mahler looking on) the climactic phrases in that tragic oration are overwhelming indeed. So too, in a quiet way, the thinning-out of the piece towards its enigmatic close, where it almost seems as if the real concluding bars have somehow evaporated, leaving it unfinished.

Which brings us to Rattle’s long and happy relationship with the Fifth – and, yes, this is yet another impressive phase in that journey. There are the things that Rattle always makes tell – the lone bassoon musing amid softly pulsing strings during the lengthy opening sunrise; the big sunburst, trumpets peaking impressively; and the longest of dancing accelerandos which is as close as this big beast of an orchestra ever gets to romping. It goes without saying that the aspirational finale is just that, culminating in the most exalted dissonance in music and final chords where the silence between is more deafening than the chords themselves.

The ‘illuminated’ opening pages of the Sixth are as beautiful as any I know – and are so here – and it is extraordinary how something so emotionally distanced can sound so moving. It remains a matter of taste whether or not there is too much flesh on the sound – concision and pellucidity are key and the finer the brushwork, the more effective in conveying the unique sharpness of the light that this music presents. The more it moves, the more rhythmic it is, the more ‘authentic’ it sounds.

But, on the plus side, Rattle and the Berliners do convey a wonderful sense of great spaces being traversed as we ‘arrive’ at the Seventh – and that journey, though compressed in time, seems to summarise a long and eventful lifetime. The most equivocal C major in music (only just) sounds conclusive and yet not. Doubtless there will be more (very different) Sibelius from Rattle and the London Symphony Orchestra. Another chapter begins.