Arcanto Quartet, Wigmore Hall, London Northern Sinfonia, The Sage, Gateshead

A letter here, an anecdote there, a series of initials spelled out in the notes of the scale.

Vexed by the mystery of genius, we love to find biographical clues in music. The Arcanto Quartet's performance of Berg's Lyric Suite began with an autopsy, tracing each stage of the composer's affair with Hanna Fuchs, from secret beguilement to whispered confessions, consummation, separation and despair in a series of discrete musical examples. Guiding your audience through a labyrinth is one thing. Making them feel each quiver of joy and pain is another.

Founded in 2002, the Arcanto Quartet is composed of four soloists, its sound uniquely strong and sweet. The voices are distinct: first violinist Antje Weithaas's bird-like, sensitive soprano; second violinist Daniel Sepec's clear, direct mezzo; violist Tabea Zimmermann's heroic, androgynous alto; cellist Jean-Guihen Queyras's slender, poetic tenor. Cast as the characters in the domestic idyll of the Andante amoroso, with Zimmermann's Do-Do (Hanna's daughter) chasing the tail of her boisterous older brother and Weithaas's Hanna calming both children, individuality is an advantage.

You can listen to the Lyric Suite without investigating its structure. If the medium is atonal, the message is High Romantic, a dissolving of two into one. Though Berg quotes Tristan and Isolde in the rheumatic lament of the Largo desolato, there is no "and" in his Allegro misterioso: his initials (A B) and those of his lover (H F, or, in the German scale, B F) dart like fireflies, muddled and reordered.

For all the sweetness and boldness, this fragment of intimacy was, with the final quiet sigh from Zimmermann's viola, more moving than any swell or sob. Schubert's String Quartet in G (D887) felt too highly flavoured by comparison. Only fleetingly was there a sense of blissful dissolving, in the autumnal drone of the Andante. The jittery Scherzo prefigures troubles to come: a haunting, a dislocation, the stuff of Winterreise and Schwanengesang. No biographical examples were needed. Within two years, Schubert would be dead.

In Gateshead, he was still young, still hopeful. A faint Gothic mist curled around Northern Sinfonia's clarinets in the opening Adagio of Schubert's Third Symphony. Was this melancholy or fantasy? Violinist and conductor Thomas Zehetmair's lithe orchestra is ideally equipped for works that teeter on the precipice of Romanticism: open to the warmest legato and the sharpest sforzandi, watchful and alert, a period-modern stylistic hybrid with an alluringly transparent blend. Having a lovely acoustic to work in helps. Much like the Wigmore Hall, where Zehetmair's own quartet will perform D887 next month, Hall One at The Sage flatters without airbrushing.

Zehetmair's approach to Schubert's Third is infused with wonder. The young composer was still working at his father's school, still studying with Salieri, when he wrote this work, one of 200 composed in 1815. Mozart and Haydn provided the structural models, Beethoven the sharp-elbowed hemiolas that pepper the Minuet. That Gothic mist is quickly burnt away by sunshine, the final movement a scorching tarantella that anticipates Schubert's on-off fascination with Rossini. Only later would he choose to explore the twilight.

The Third Symphony was not performed in Schubert's lifetime. Neither was his fourth, with its ill-deserved soubriquet, the Tragic Symphony. This is a fan letter to Beethoven's fifth, adopting the same interrogative play of minor to major, dark to light, the same key. Zehetmair cuts an intimidating, austere figure on the podium. Yet his string players seemingly thrive on details of bowing that only a fellow string-player would demand. The details are dazzling, violas and second violins giddy in the teeth-chattering quavers of the last Allegro, the intelligence and wit of the cello section captivating throughout.

So, from a fan letter to the most enigmatic four-note motif in the canon. In Zehetmair's reading of Beethoven's Fifth Symphony, the famous opening was less a statement than a whiplash double-take. Northern Sinfonia's fight-or-flight performance was notable not just for the specificity of phrasing – instead of allotting short bows to one subject, long bows to another, their bowing develops in parallel with the musical development – but for the breadth of space in oboist Michael O'Donnell's solo cadence. Bees hummed in the Andante, the ground shook in the transition to the closing movement, its great affirmation underpinned by a handsome contrabassoon. Intensely familiar and shockingly new, this was more vivid and enthralling than the Leipzig Gewandhaus's recent Beethoven. A triumph.

Next Week

Anna Picard encounters a Winterreise involving a puppet

Classical Choice

Ex Cathedra sing Christmas music by candlelight at St Mary's, Warwick (Tue), St John's, Hagley (Wed), St John's, Smith Square, London (Fri), and St James, Chipping Campden (Sat). The EU Baroque Orchestra brings A Breath of Enlightenment to Spitalfields Winter Festival with Locatelli's Christmas Concerto in London's Shoreditch Church (Sat).