The sense of a sea change is undeniable — for the musicians and audience alike. In the space of less than a week, new music director Ludovic Morlot has demonstrated the potential to open not just a new chapter but a new era for the Seattle Symphony.

A steady crescendo of pre-season decisions and appearances heightened anticipations about what to expect. The organization has gone out of its way to rebrand itself with a new logo and tagline (the Star Treky “Listen Boldly”), while Morlot’s first two appointments were announced over the summer: Demarre McGill, formerly with the San Diego Symphony, as principal flute, and principal cellist Efe Baltacigil, who transferred from the Philadelphia Orchestra. For the first time in its history, the SSO joined the lineup of the Bumbershoot arts festival with an eclectic grab bag of pieces showcasing Morlot and a handful of players.

But all the talk about rebooting the SSO and setting new community-serving priorities is one thing. The real test, the actual music-making in Benaroya Hall, has also begun. Judging by the first two programs of his inaugural season, Morlot has left substantial and encouraging impressions that he has the goods to translate all the lofty plans into tangible and desired results.

Saturday’s opening night concert was typically glittery and featherweight, but it had some indications of a genuine artistic manifesto. Morlot conveyed some key messages about his interpretive style, his programming philosophy, and his rapport with the ensemble —  along with a few weak spots that are hardly surprising for a young conductor undertaking his first permanent directorship of an orchestra. (At one point he charmingly compared the commencement of his tenure to the frisson a violinist feels “when he opens the case of a Stradivarius he knows he will have on loan for several years.”)

A native of Lyon, France, the 37-year-old Morlot (accent on the second syllable) is a gifted communicator. Without question, the overriding feeling that lingers after these first two concerts is the sense of warmth and enthusiasm with which the musicians respond to his energy. It forms an inspiring feedback loop that has the SSO playing with a new focus and conviction. That was the case even when the music in question wasn’t particularly compelling, such as Beethoven’s "Consecration of the House" overture from 1822, which launched opening night. Beethoven’s overwrought, neo-Handelian counterpoint makes much of the score sound like a study, yet at strategic points Morlot had the players rally with excitingly explosive bursts of energy: a foretaste of their "Eroica" symphony to come a few days later.

Morlot’s animated podium style covers a large range of gestures, postures, and signalings. It’s enthralling to watch. This isn’t about a display of ego, with the orchestra as some vast projection of his personality, but rather the conductor homes in on the sheer wonder of collective music-making that seems to motivate him. It made me think of an exuberant tour guide — a role Morlot seemed particularly to relish as he led the SSO in an engaging account of Gershwin's "An American in Paris." (It can be heard again during the last week of September when Morlot will pair the piece with Stravinsky's "The Rite of Spring.")  The tired charges of Gershwin’s alleged awkwardness with “large forms” were breezily swept aside as Morlot dug into the rhapsodic spirit of invention and discovery that crackles through this pre-Depression score.

The all-important connection Morlot is establishing with the orchestra emerged as the real subtext of the concluding item, Ravel’s "Boléro." The sinuous freedom of the melody that’s passed from one instrument to another was heard to chafe against an insistently mechanical, unyielding rhythmic track (commandingly laid down by Michael Werner on snare-drum). This was a neat metaphor for the tension between spontaneity and control that enlivens live orchestral performance. To emphasize the point, Morlot indulged in a bit of gimmicky theatrics, abandoning his post at the podium to join the orchestra for a few minutes as he took up his own instrument, the violin.

The biggest misstep of the opening came with the Cello Concerto of Friedrich Gulda from 1980, chosen to represent the much-heralded attention to new music and unexplored repertory that promises to be a signature of Morlot’s tenure. In introductory remarks, the conductor showed himself to be an affable spokesman for open-minded listening. But the piece itself left a dreadful aftertaste. Gulda, an Austrian pianist who had a remarkable career bridging the classical and jazz worlds, seemed to be aiming in his Cello Concerto for a Dada-like pastiche, plunging down one stylistic rabbit hole to the next, from (annoying generic) jazz-band and blues to mock-naïf folk and circusy Sousa march.

Far from “edgy,” the piece comes across as an exercise in derivative kitsch. Joshua Roman, former principal cellist with the SSO and currently pursuing a solo career as well as serving as music director for Town Hall's music series, seemed to buy into the Concerto, whose lengthy cadenza movement contains the most interesting passages. But for all the extended technique and personality Roman generously lavished on the Gulda, the payoff simply wasn’t there. The whole endeavor felt like an effortful exhortation to have “fun.”

All the clichés about “crossing boundaries” aside, this sort of faux-populism is inherently stodgy and unadventurous. Fortunately the SSO’s first Masterworks program of the season on Thursday night (repeated this Saturday night and Sunday afternoon) provided a more substantial measure of Morlot’s chops when it comes to new music, along with his genuine flair for creative programming. The first half was given over to "Dupree’s Paradise" (1983), one of a trio of pieces Frank Zappa originally prepared for Pierre Boulez and the Ensemble Intercontemporain. It incorporates music Zappa used in concerts going back to 1974 to introduce his band as they improvised around it. Zappa liked to compare his classical compositions to Calder mobiles “dangling in space,” but in its full orchestrated format, "Dupree’s Paradise" conjures a beatnik serialist on a lost weekend. (You can get another take from Bruce Bickford’s claymation film version.) Morlot had the SSO tap into its exuberant energy in a way that had its echo in the second half, with its drivingly maverick Eroica."

Zappa’s steely, shiny orchestration also made for an intriguing contrast with what followed: "L’arbre des songes" (“The Tree of Dreams”), Henri Dutilleux’s exquisite violin concerto from 1985. Still composing at 95, Dutilleux is a major voice in French music of the past half century but has been hitherto overlooked by the SSO. Morlot plans to explore more of his work later in the season.

L’arbre provides a savvy entrée into Dutilleux’s intoxicatingly beautiful sound world, one crafted with the kind of obsessive perfectionism Flaubert directed toward his search for “le mot juste.” It’s intricately veined and layered and yet — especially in the rapturous yet tightly focused performance given by French violinist Renaud Capuçon   — suffused with a sensual eloquence that places it on the more “accessible” end of the spectrum for a first encounter. Morlot was entirely in his element and shaped the piece as if he were regulating the metabolism of a mysterious, dream-like creature.  The SSO responded with sparkling, gemlike clarity of timbre.