The challenges that Birmingham Philharmonic Orchestra sets itself are never anything short of daunting. These amateurs play with immense conviction and self-belief, the warm rapport and support shared by all of them keeping hubris well at bay, and one can listen with confidence as they tackle awesome giants of the repertoire.

And they don’t come much more awesome than Mahler’s complex, painfully-wrought Tenth Symphony. There is so much baggage here: the technical difficulty of the dots themselves; the fact that it’s not all out-and-out Mahler, despite the empathy of Deryck Cooke’s completion; the grim fact that Mahler knew his health clock was running down as he desperately sketched the work; and the heartbreaking discovery that his adored wife Alma was having an affair with the architect Walter Gropius.

Yet this was a reading from the BPO which confronted everything head-on, emerging triumphant after 75 minutes of sustained concentration in front of a gripped audience which never dropped a pin. Under Michael Seal, a conductor who has developed so gratifyingly from one of calm efficiency into an interpreter genuinely with something to say, the music was shaped and developed with a cogency which both looked back to earlier works and anticipated the expressionistic contortions of a later generation.

Full marks to the violas for the way they tackled the exposure of the opening (Simon Rattle - under whom Seal will have played the work - made his CBSO violists have a last-minute rehearsal on Symphony Hall’s dressing-room corridor). The finale’s important, life-changing flute solo was beautifully delivered by John Franklin after Katy Francis’ brusquely emphatic bass drum thumbs-downs, and everywhere the individual lines of this virtual chamber-music score (despite the huge orchestra) intertwined persuasively.

Of course there was the occasional blemish of intonation and lapse in ensemble. But these didn’t matter. Seal and the BPO gave us a Mahler Ten of unforgettable communication.