This was a symmetrical programme where late onset, minor key symphonies, flanked a concerto whose tonality seemed a minor concern.

Finnish Clarinet soloist Kari Kriikku, in pre-concert conversation with RSNO violist Katherine Wren, explained that the 2002 Clarinet Concerto of his friend and compatriot Magnus Lindberg was greeted as a departure from a previously more stridently avant garde style. True, it opens with unaccompanied soloist in minor pentatonic mode, but soon broadens into a dazzling kaleidoscope of harmonic fluidity and orchestral colour. So captivating is the orchestration that, even minus the concerto element, this essay in instrumentation would keep students of the art busy for months. Søndergård and the RSNO controlled the single-movement work's 28 shimmering minutes commendably.

Kriikku, for whom the work was written, was as entertaining on stage as he'd been in the humorous talk. My view of him obscured considerably by a handrail, I was conscious of disturbing others by moving about too much in my efforts to fathom the magical noises emanating from the clarinet. However, seeing how much the sometimes elfin Kriikku moved, I soon relaxed. More than once he was centimetres from genuflection; stances altered; feet lifted; at one point he journeyed round behind the conductor to play at/with the cello section. Traditional virtuosity mingled with extended techniques: multiphonics (upwards of two notes simultaneously); singing whilst playing; extensive glissandi; playing of such quietude that keypad noise was the leading sound; tinnitus-inducing fortissimo notes. This is a dazzling work which I'd urge anyone to seek out and the vocal response in Usher Hall suggested that this audience had been thrilled. Touchingly, Kriikku acknowledged the RSNO clarinet section with whom he'd engaged in distant dialogue.

Sibelius' Symphony no. 6 seems to be his least played and recorded. It certainly lacks the heroic gestures of its predecessor but then its raison d'être is entirely different. Sibelius aspiration to "offer the public our cold water" could be heard in the clarity of the opening bars, although the lovely warmth of RSNO strings was undeniable. I felt that Søndergård and the RSNO had the measure of this most organic of composers in the way the movement gradually broadened out. Any isolationist, Finnish take on this music could arguably be countered with similarities and influences in opening Allegro molto moderato. I felt resonances of Warlock, Holst and, in more animated moments, Petrushkan Stravinsky. I later felt the spirit of indeterminacy à la John Cage when, in the silence following the movement's minor/major deliberations, a doh-mi-doh-mi ringtone chimed in favour of the latter.

The uncommon pairing of flutes and bassoons paved the way for a second movement, an Allegro moderato full of unusual colour with notable contributions from harp, pizzicato basses and five horns. Users of the musical notation software, named for the composer, would have recognised the movement's closing bars as the program's opening signature.

The tick-tock opening of the Poco Vivace soon gave way to music of much greater virtuosity and I noted Søndergård smile at the impressive energy of the upper strings. Muscular RSNO brass also featured when five horns teamed up with three trumpets and trombones. The work ends quietly and, given the turbulent background described in David Kettle's fine programme notes, it's perhaps not surprising that such an end might appeal to Sibelius. There were certainly some lovely woodwind and string sounds towards the close of this rendition.

Tchaikovsky's Symphony no. 6 in B minor "Pathétique" was an even later event in his life than was case for Sibelius and he died days after the première. This fact, coupled with the symphony's sobriquet, has led many to stray in their impression of the work from the Russian "patetichesky" meaning "passionate" or "emotional". There was certainly plenty of commitment in this performance, whether in solo moments such as David Hubbard's fine bassoon opening, sectional features such as the horns' suitably waspish contribution to the Finale, or the many finely balanced tutti sections throughout.

Facing the cellos, I became aware of the many marvellous melodies and countermelodies they enjoyed. In combination with the basses, they also contributed to many gripping pedal moments whose relentlessly repeating notes furnished, contrastingly, mounting tension or joyous contentment.

Such is the riotous end to the third movement, Allegro molto vivace, that Søndergård wisely attacked the Finale: Andante lamentoso - Andante without pause. The phrasing of the strangely scored opening string writing (one of music's great audio illusions – the tune that isn't really there) was beautifully phrased, as was the later, more Elgar-like string theme. At the movement's conclusion, Søndergård held the framing silence for a remarkable length of time before relaxing shoulders cued warm and energetic applause.