Undeterred by two scheduling disruptions thanks to COVID-19, the Spokane Symphony’s former music director, Eckart Preu, was at last able to rejoin the orchestra Saturday night for a concert in its Masterpiece series.

Before consulting with James Lowe, the orchestra’s current music director, Preu had in mind to feature a symphony by one of his favorite composers, Anton Bruckner: Symphony No. 3 in D minor. To fill out the program and offset the seriousness of Bruckner’s 50-minute work, Preu thought to include some lighter waltzes and polkas by Johann Strauss and others that were popular in Vienna at the time Bruckner was living there.

Lowe countered, however, with the idea of starting the evening by performing the Prelude and Liebestod (Love-Death) from Richard Wagner’s opera, “Tristan and Isolde” (1865). Bruckner idolized Wagner and traveled to Bayreuth, Germany, to attend the opera’s premiere. While there, he met the composer and offered to dedicate to him his newly finished Symphony No. 3. Lowe felt that this made the two pieces ideal companions on a concert program, and his idea prevailed.

The 54-year-old conductor who stepped onto the stage Saturday night was not greatly changed from the one who led the orchestra for 15 years. The tireless energy, constant focus and emphasis on propulsive forward movement were all intact. They seemed to be enriched, however, by a greater willingness to caress a phrase or balance a brief passage to achieve exactly the right color. One also noted an increase in patient willingness to allow a passage to reveal itself at a tempo arising from within itself, rather than imposed from without.

These differences, if indeed they were different, were complemented by a refinement in Preu’s conducting technique – a greater independence of his hands – that permitted him to communicate more precisely to the players the expression he wished to be applied to a key phrase or passage. New or not, these aspects of Preu’s conducting were exactly what the music needed and resulted in performances rich in exquisite detail that never lost their sense of compelling destination, nor allowed the variety of the composers’ imagination to descend into incoherence.

Despite Bruckner’s reverence of Wagner, which led him to include numerous quotations from Wagner’s operas in the original version of his Third Symphony, the two men could hardly have been more different. Wagner was a man of the theater, enormously gifted in portraying the complexities of human nature, sinister as well as heroic. He became increasingly absorbed in the process of unifying and consolidating. This resulted in his concept of “gesamtkunstwerk,” or “total artwork,” in which all of the arts – poetry, dance, music and design – are combined in a single entity, which he termed “music drama.” “Tristan and Isolde” was Wagner’s first work that completely expressed this conception.

Bruckner, on the other hand, was a man of the church who took pleasure in the delights of this world as foretastes of the pleasures that God held in store for the virtuous.

What they held in common, however, was a capacity to enlarge and exploit the sonic capabilities of the symphony orchestra, as well as a determination to expand traditional strictures of harmony and musical form. Both composers felt a need to sustain a musical argument, and maintain the attendant tension, over much longer spans than their forebears could ever imagine. Beethoven begins his First Symphony with a dissonant chord that resolves in the next measure. “Tristan,” however, begins with an unstable chord that does not resolve until the end of the opera, 4½ hours later. The Prelude and Liebestod snips off the first few minutes of the opera and combines them with the final few minutes, but that is enough to allow us to feel the yearning for resolution that mirrors the dilemma of the lovers, Tristan and Isolde, who long to consummate their love, and finally welcome death as the only remedy.

In Saturday’s performance, Preu perfectly balanced the score’s demands for both expectant stillness and inexorable forward movement. When the music – and Isolde – reaches its climax, the effect on the audience is shattering. During the course of the piece, one could savor both the hypnotic beauty of individual solo contributions from Keith Thomas, oboe, and Chip Phillips, clarinet, and the sumptuous blend off all choirs of the orchestra. Another of Preu’s signature attributes contributed to this: his ability to draw a blended, saturated tone from the orchestra, as distinct from the more aerated transparency favored by Lowe. The ability of the orchestra to adapt to the demands of different conductors is proof of consummate musicianship.

Making the shift from Wagner’s disciplined economy of means to Bruckner’s boundless fecundity was like turning a corner in the gardens of Versailles to find oneself in the Amazon rain forest. Furthermore, Wagner’s unbroken arc of tension from the beginning to the end of the work was replaced by Bruckner’s characteristic cycles of tranquility-anxiety-exultation with little or no transition. Rather than attempting to enforce unity on his spurts of improvisatory inspiration either by rushing from one cycle to the next or, conversely, by slowing the tempo to a crawl, Preu allowed just enough time for each segment to express its unique character, and, thus, justify its place in Bruckner’s enormous tapestry.

While Wagner uses brass and winds to color what is primarily a string-based orchestral texture, Bruckner assigns to the strings the task of embellishing and enriching the statements primarily of the brass and, to a lesser extent, the winds. Thus, the stamina, flexibility and tonal beauty of the brass section of the orchestra were challenged as they are in no other corner of the symphonic repertoire. There was scarcely a measure that did not call on the horns, led by Charles Karschney, the trumpets, led on this occasion by Charles Butler and the trombones, led by principal John Church, to pour out unstinting flows of rich, exciting tone. They ended the piece, as did all onstage, covered in glory.