On an evening in April last year, I attended a Toronto Symphony Orchestra performance at Roy Thomson Hall. I hadn’t been to a concert in a long time—blame it on mid-life inertia, I suppose, along with a negative impression of the TSO I’d acquired after a decade of bad news, both financial and artistic. I went because I was curious to hear the rarely performed Turangalîla Symphony by the French composer Olivier Messiaen, and the tickets were only six bucks, thanks to an on-line promotion.

Those six-buck seats turned out to be in mid-orchestra. The hall was packed, and there was a noisy buzz while the players were taking their places onstage.

Despite predictions of its death, the TSO is playing regularly and beautifully to near-capacity audiences; musicians and staff are still basking in the glow of a sold-out, critically acclaimed performance last October of Shostakovich’s Eleventh Symphony at New York’s Carnegie Hall. The Times reviewer managed to cram “wrenching,” “full throttle,” “superb,” “world class” and several other enthusiastic adjectives into a single paragraph, and the Globe and Mail critic referred to the “throaty bravos” and “five-minute standing ovation.” After eight years without a compact disc to its credit, the orchestra released three last year, on its own label, and made them available as downloads from its Web site.

The most astonishing development, for anyone who might remember the symphony audience as a kind of waiting room for that big concert hall in the sky, is the age of the audience members: one in five is under 30, and the average age dipped below 50 last year—the youngest it has been in decades. You can feel the difference in the hall. High school and college kids are there on dates. The post-concert parties in the lobby, which rarely risked anything more musically daring than a jazz ensemble, have been featuring such local indie performers as the Roaring Girl Cabaret, Autorickshaw and Laura Barrett.

At that concert in April, the musicians delivered a soul-shaking musical experience. There were moments when I wanted to laugh out loud from giddiness and glee. Turangalîla is an eccentric work, over an hour long, in 10 movements, requiring a huge orchestra, a piano soloist (they had Marc-André Hamelin, so they had the best) and enough percussion to gladden a head­banger. The score calls for an ondes Martenot, an early electronic instrument, which contributed swoony outer space sounds and imitated cuckoo bird calls. The music can sound like Gershwin on Ritalin and then almost lavishly Hollywood and then spikily modern and then come together in an overwhelming, percussion-drenched climax. I was waiting for the work to end that way, with a great, satis­fying clatter of drums and cymbals; but instead the music paused for a moment, and then the orchestra breathed a chord that seemed to contain every colour in the universe and every sound ever uttered since the dawn of time.

Then it stopped. And so did the audience, for just a second. Then we were on our feet, hundreds of us, shouting wildly or too choked up to make a noise.

You can’t get that kind of experience on your iPod.

The birthdate of what we know today as the TSO is April 23, 1923, when a group known as the New Symphony Orchestra played its first concert at Massey Hall, performing works by von Weber, Dvořák, Brahms and Tchaikovsky. Luigi von Kunits was the founder and music director, and remained so until his death in 1931 (by which time the name had been changed to the Toronto Symphony Orchestra). The TSO has always been dependent on a variable mix of government support, the largesse of wealthy patrons and philan­thropists, volunteer organizations, corporate sponsorships and, of course, ticket sales. TSO archivist Richard Warren, in a history of the organization, traced the funding problems back to the 1946-47 season. “Financially,” he wrote, “the orchestra was about to face what would prove to be a continual challenge: the difficulty of convincing the different levels of government of the importance of their financial support.” The accumulated deficit had reached $4,144; nonetheless, that season was successful artistically. There were more than 100 concerts, and this not long after the war. A 14‑year-old pianist named Glenn Gould dazzled in a performance of Beethoven’s Piano Concerto no. 4. The illustrious baritone Lawrence Tibbett was a guest artist.