When Bruckner decided, in his early 40s, that he was going to be symphonist, although he didn’t turn his back entirely on sacred choral music his overwhelming and ceaseless endeavour was to produce abstract symphonic music for the concert hall. His greatest completed work, in terms of aspiration and duration, is the mighty Eighth Symphony, a work of such towering proportions that it is often best presented as the sole item in concert programme. But it seemed an inspired idea of the BBC programmers to include in the first half of the concert some of Bruckner’s short, unaccompanied motets – Locust iste, Os Justi, Christus factus est and Ave Maria.

In the event, dragging these little jewels from their intended ecclesiastical context into the concert hall provided a rather clinical context, the meaning of the words hardly able to signify anything that might give us pause for thought. But they were very beautifully sung, the dynamic range extensive with climaxes loud and strong enough to have come from one of his symphonies, and the quiet endings in each case hushed and exquisite. They were preceded by the extended Bach motet Jesu meine Freude which, for all its beauties and moments of dramatic virility, as in the forceful clarity of “Trotz dem alten Drachen” (Despite the old dragon), seemed like a sermon that outstays its welcome, belying its title by having precious little that was joyful until its very last phrase.

What a contrast and such an exciting buzz to return to the hall after the interval and find the little choir replaced by a stage crammed full of musicians, the three harps that Bruckner requests “if possible”, and a full array of brass, plus Wagner tubas, triple woodwind, large strings sections, all loudly tuning up. In what turned out to be a courageous evening, they performed like heroes. I have rarely heard the BBCSO perform Bruckner so well since the days of Günter Wand. Right from the very opening, at a simple gesture from Leif Segerstam, a closed fist suddenly opened, pianissimo string tremolo and horns came in precisely together.  This is so rare, as the horns usually take a moment to sound and the opening can often be ragged. And then, after the statement of the theme in the bass, the oboe comments with a falling phrase, encouraged by Segerstam with open arms to expand its expressive potential towards the deepest of tragic laments, and it was apparent that this performance would endow its encounter with this music with widest spectrum of profound emotion. Oboist Richard Simpson, in all his recurrent telling solos in this movement, gave us music-making of heartfelt eloquence.

With the entry of the rising, lyrical second theme on violins, it was hard to believe that we weren’t in the presence of one of the continental European orchestras famed for their Bruckner. The rich, dark sound Segerstam had drawn from the orchestra was something I didn’t know was possible in the Barbican Hall acoustic, and the orchestral playing from all sections was near faultless over the immense and ultimately exhausting span of the work.  Segerstam had slowed down drastically through the development section of the Finale – indeed, he was very slow at the heart of the other movements too – which gave opportunities for really well defined rhythmic attack from the woodwind and brass, and the flute and clarinet ornamentations of the finale second theme were spelt out beautifully, flautist Daniel Pailthorpe was exemplary throughout. The brass, even though required to play at times long and very slow, were magnificent and rhythmically taut, their ‘Annunciation of Death’ climax in the first movement shattering in its dramatic impact.

Segerstam’s interpretation was unapologetically uncompromising. He didn’t mind how long it took – and it took a very long time – there was no fuzzing of the issue here, the enormity of the drama with which this symphony concerns itself was confronted full on. Having heard the symphony many times, I have ideas about how it should be done, and Segerstam wilfully offended against nearly all them... but with total conviction. The quiet end of the first movement, following Bruckner’s description, should be the remorseless ticking of the clock where a person lies dying, so no slowing down, no diminuendo, and none is marked in the score; but Sergerstam did both, so that instead of a clock we heard the dying of the tremulous heart beat as the protagonist expired – a slowing down absolutely perfectly synchronised by the BBCSO violas. The final notes of the whole symphony, the same falling phrase writ loud and large, although marked with a ritardando, I feel always needs a short crotchet to close, to give an effective finality; but Segerstam held it long and firm, and it worked perfectly.

There isn’t room here to detail all the extraordinary events that gave this immense performance its overwhelming power, succeeding through suffering, brutality and bereavement to triumphant apotheosis, and not everyone in the audience found themselves able to go along with it. One in the hall had felt it worth enduring the whole 105 mins so as to be able to boo loudly at the end, but for me it will stand out in memory alongside other outstanding London Eighths, not least for the transfigured BBCSO, which responded to Segerstam’s exceptional and taxing demands with absolute commitment and astonishing beauty of sound.