For 33 summers now, the Seattle Chamber Music Society (SCMS) has been presenting an extensive festival that now ranks as a particularly desired destination for musicians on the summer chamber circuit across North America. This latest edition is off to an especially invigorating start. For their part, the audiences tend to be uniformly enthusiastic and devoted, but last night's performances met with vociferous approval that reached the extreme end of the applause-meter.

The unusual programme design – juxtaposing Stravinsky's infrequently heard Octet for Winds with bread-and-butter classics by Mendelssohn and Beethoven – is a signature of James Ehnes, now in his third year as SCMS's artistic director.

Ehnes was hand-picked by SCMS founder and cellist Toby Saks – one of the first female musicians in the New York Philharmonic, among many other accomplishments – and came of age as a violinist playing for the festival since the 1990s. Saks died suddenly of cancer just after the conclusion of last summer's festival; the current season is dedicated to her memory.

Overall, this summer features a refreshingly innovative blend of familiar repertoire with vocal chamber pieces as well as orphans by well-known composers. The performances are held in the Benaroya Hall complex downtown, home of the Seattle Symphony, but in the more-intimate Nordstrom Recital Hall (c. 540 seats). The dry acoustics exaggerated some of the harsher edges of the Stravinsky Octet, which opened the program.

The Octet is scored for a formation of flute, clarinet, and pairs of bassoons, trumpets, and trombones – but part of the excitement of the piece is how these 'realign' into ever-changing coalitions throughout. Recognised as a significant early instance of Stravinsky's post-Great War neo-Classicism (though read about more than heard),  the Octet manifests the composer's famous rejection of music as 'self-expression': it is “not an 'emotive' work but a musical composition based on objective elements which are sufficient in themselves,” Stravinsky declared.

On a more practical level, the Octet served as a vehicle for Stravinsky to cultivate his skills as a conductor; it was the first of his works that he himself introduced in that capacity (in Paris in 1923). For this performance there was no conductor, which may account for the relative lack of a more architecturally persuasive sense of the Octet's structure, in which each of the three movements pays Stravinskian (i.e. ironic) tribute to a different classical form – one of the piece's 'objective elements'. 

The playing itself was superb; clean and alert, with jaunty ensemble attacks and continual subdivisions into smaller units – pairings, trios – that gave tangible shape to Stravinsky's sculptural constructions. The bassoonists executed the cruelly difficult perpetual-motion figures with poise, and trumpeter Jens Lindemann's attacks were jauntily bright, enhancing the funhouse aura of the Octet, in which Stravinsky winks at popular idioms.

The dry, block-like sound world of the Octet set up an interesting context by way of contrast with the ensuing account of Mendelssohn's beloved Piano Trio in D minor, Op.49. In addition to the beauty of the Mendelssohn performance in itself –  its passionate conviction swaying the scales toward the Schumannesque, Romantic side – this was a delightful reminder of the intimate pleasures of chamber music-making.  

The Scherzo, for example, proved an object lesson in nanosecond decision-making as the three musicians volleyed and richocheted motifs against one another, a game of firefly tennis. And particularly in the agitated outer movements, the chemical reaction of pianist Jon Kimura Parker, violinist Augustin Hadelich, and cellist Efe Baltacıgil (principal cello of the Seattle Symphony, one of several SSO musicians on the Summer Festival roster) supplied emotive fire to counteract the putative objectivity of Stravinsky's Octet.

The Andante found Baltacıgil and Hadelich using poetic phrasings to make deeply personal statements, while at the same time urging the music on with purposeful synergy. Parker gave stylish momentum to the formidable piano part, overwritten as that part at times unavoidably sounds.

As a special treat, Ehnes performed Beethoven's C minor Quartet from the Op.18 set with his own quartet in a free recital before the concert proper; they then returned for the work filling the evening's second half, the very substantial “Razumovsky” String Quartet in F major, Op.59, no. 1. European audiences tend to know Ehnes's artistry as a soloist, but earlier this year he embarked on his first tour to London and Paris with the Ehnes Quartet, an ensemble of friends and colleagues who have played together for years at the Seattle festivals.

Here was a somewhat different, though equally enthralling, approach to the chamber ensemble ideal: instead of three very distinctive personalities merging together, a quartet of more like-minded musicians in which Ehnes often seems the “first among equals”, setting the tone and guiding the overall spirit.

The language he and violinist Amy Schwartz Moretti, violist Richard O'Neill, and cellist Robert deMaine speak together – one marked by lyrical clarity and a real sensitivity to dynamic contrasts – feels so assured that impulsive, spur-of-the-minute choices can be readily accommodated. There's a clear sense of risk-taking, of going beyond whatever happened in the last rehearsal, such that their performances are imbued with a remarkable vitality. Some moments of imprecise ensemble may result, but the tanginess of expression is more than worth it.

And there was admirable long-range thinking in these performances: they launched the Op.18 quartet with a subdued demeanor calculated to maximise the dramatic effect of what unfolds. Their Razumovsky was especially satisfying, bringing out the sheer strangeness of this music, for example, in the epic digressions of the Allegro (at moments it seemed we were already listening to one of the late quartets). Their pacing enhanced the emotional depth of – and consoling contrast within – the Adagio, but without negating Beethoven's huge, eccentric humor in the intervening scherzo. 

For any music lovers planning to be in Seattle between now and 2 August, it's worth considering the variety on offer over these coming weeks from the Summer Festival