The Zurich schools’ summer holidays had just begun, the weather outside was gorgeous. What’s more, the first semi-final of the European Soccer Championships were being broadcast that same evening on TV. So while Jörg Widmann was this Tonhalle season’s “Creative Chair”, and concerts that included his works had regularly met with interest, the Tonhalle being three-quarters full on this particular evening came as something of a surprise.

Much of the interest lay in Mozart’s Clarinet Concerto, one of the master’s final completed works, which − in the hands of an absolute virtuoso − was first on the programme. The concerto was originally written for a basset clarinet − a rare, custom-made instrument, whose occasional and deliberate dissonances many late 18th-century “gentlefolk” found grating. The young Mozart liked it nevertheless, and wrote this stunning concerto widely known today for its delicate interplay between soloist and orchestra, and lack of extrovert display in the clarinet part. The work’s calculated dissonances might also be said to foreshadow musical genres Widmann himself would draw upon as a composer.

But in Zurich, he played the role of soloist first. In the concerto’s first movement, a “lightness of being” and happy romp gave way to the lower tones of a thick and heavier orchestral brocade, ever returning to more breathable fabric. Widmann’s fingerwork is unparalleled; he scoots over the keys with the ease of a friendly conversation, but also extracts tremendous pathos from his instrument. Paced more slowly than usual, the second movement’s sustained and elegiac melody cradled us all  – not a peep in the hall throughout – and there were variations in volume by the clarinettist and orchestra alike that moved from the silvery tones of the flute to the pianissimo of the final orchestral sequences.

Encouraging the cellists to catch up with his accelerated tempi, the conductor smiled widely at them as the third movement began. He twice hopped on one foot. His whole body moved in its direction like the repeating “O”s of a calligraphic exercise, but – hands tied as they were – he also relied on the seasoned guidance of the first concertmaster. Klaidi Sahatci’s clean and emphatic cues shaped the work even when Widmann was adjusting his instrument’s mouthpiece, wiping his mouth, or simply basking idly in the sound.

Before the concert, the some 150 seats temporarily “parked” at one side of the Tonhalle’s foyer suggested something big would follow the Mozart. The hall’s three front rows had been moved for the stage to be extended for a huge orchestra configuration. Jörg Widmann’s own Messe promised some serious volume and fanfare. And deliver, it did.

As the last work in Widmann’s trilogy for orchestra, Messe explores the projection of vocal forms among instrumental ensembles. In brief opening remarks, Widmann explained that the work’s form of singing would translate into the absence of solo vocalists and chorus. Later, the individual “voices” in the 45-minute performance showed a distinctly democratic approach to the various instrument families: the horns were highlighted, but overall, no less so than the ten cellos, the flute, the piano, the accordion, the strings and percussion. It was, in a sense, everyman’s band.

Widmann had also invited us to join his “musical journey”, one meant to underscore man’s struggle with his God, and portray the godly “counterpart” that represented a Passion. Yet even with that information at hand, I had trouble following for lack of directional signage and any landmarks along the way. For me, the orchestral “singing” bordered on cacophony. Expansive and tremendously loud passages were borne as irregular outbursts along the path: gong, cymbals, horns, and tympanum all in shining regalia, the players sometimes dredging up fragments of old hymns, then tearing them entirely asunder. I want to surprise even myself,” Widmann had said, “…stringently working through the concept in every single composition.” Point taken: but then out of the blue, what sounded like a large wooden box slammed onto the floor, followed in short order by a sustained tinkling of a violin. I ordinarily embrace the modern, but was simply lost in the forest for all of the trees.

Not to suggest that the performance was without merit. The orchestra played tightly and moved form one haunted, loaded fragment to another; the Hammond organ lent a cinematic spookiness to the score. The double bass, too, sounded murky and ominous, and there were shrill tones I readily equated with profound grief. Further, if the strings cascading down the scale suggested “The Fall”, then this was as much of a theatrical piece as it was supernatural story, the ticking clock and the sounds of the wind tunnel adding a otherworldliness to the host of “voices”, each instrument whispering its enigmatic catechisms.