One problem about living high on the hog is that sooner or later you have to move down to the rest of the hog. Two weekends ago, I had one of the great musical experiences of my life. The world’s most important living musician with a hyphenated career, conductor-composer Pierre Boulez (or is it composer-conductor? — which comes first is the question Boulez has been asking himself) led a series of three concerts with the Vienna Philharmonic Orchestra at Carnegie Hall (the most recent of this great orchestra’s four Boston appearances since 1956 was in 1993). The high cost of these concerts was “underwritten” by millionaire/connoisseur Alberto Vilar, and the top seats were still an astronomical $176 (the top price for Bernard Haitink and the BSO at Carnegie this past weekend was $85). Yet the concerts were virtually sold out. Even if I’d had to pay for my ticket, it would have been worth every C-note.

In September, the 76-year-old maestro is taking a year-long sabbatical to compose, especially to complete the orchestration of his piano series Notations. At a reception after the second concert, he even speculated about the possibility of writing an opera. His dazzling 45-minute Sur incise (based on his four-minute 1994 piano piece Incise), which he worked on from 1996 to 1998 and which received a splendid performance at Tanglewood last summer, just won what is probably the most prestigious award in music, the $200,000 Gravemeyer Prize. (It’s now on a marvelous new DG CD with the Ensemble InterContemporain.) In New York, I was invited to a rehearsal for a concert of Boulez music by the superb Ensemble Sospeso that was to be presented at Alice Tully Hall as part of the avant-garde series “Works & Process at the Guggenheim.” I asked one of the musicians what it’s like rehearsing with Boulez. “Everything he said makes sense,” the musician told me. “It’s extremely obvious he knew exactly what he was doing and hears exactly what he writes. He could be God — or the Devil.”

Boulez the conductor also happens to be at the very top of his form. Last year he led an extraordinary series of concerts at Carnegie Hall with the London Symphony, in which he surrounded brand new pieces, including one of his own, with masterpieces of late Romanticism and early Modernism — works that interest him as the seeds of contrasting aspects of contemporary music (Schoenbergian chromaticism on its way to the annihilation of tonal music; Stravinskyan polyrhythmicality; sound color as structure, as in Webern). This year, with the astounding (and anachronistically still virtually all-male) Vienna Philharmonic, the most recent work was Stravinsky’s post-World War II Symphony in Three Movements, which capped a program of music that premiered during the seminal years of 1912 and 1913.

From the sweet swing that swept through the first bar of Bartók’s rarely played Four Pieces for Orchestra, as if dawn sunlight had just flooded the earth, you could hear the exceptional quality of this musicmaking. I’m not sure how else to put it — this is an orchestra of infinite depth, not only as in bottomless resources of talent (which it has — at the rehearsal of Mahler’s Third Symphony, the players broke out into applause after the stunning first-movement trombone solo) but also as in “3-D,” a depth of sound — layers upon layers in which every line, from ethereal highs to cavernous lows, is clearly audible, a quality that is also a particular specialty of Boulez. No aural wallpaper at these concerts.

The Bartók, like everything else Boulez chose, is a work of mercurial contrasts, even within each movement (the Scherzo alone ranges from slash-and-burn brass to Brahmsian waltz), and no surprising musical turn was left unacknowledged. Webern’s brief Six Pieces simmered, then sizzled with mystery and (yes, even in Webern) drama, as in the way the slow cortège of fourth-movement funeral march built from near silence to ear-shattering apocalyptic crashes.

After intermission, Boulez led a piece he has long championed: Jeux, Debussy’s music for Nijinsky’s tennis-game ballet (a sexual ménage à trois), now near-forgotten, probably because it premiered the week before the riot that greeted Stravinsky’s Le sacre du printemps. Like late Verdi in Falstaff, Debussy in Jeux abandons the big themes of, say, La mer for subtle, suggestive, seductive sound fragments. Jeux is less “play” than “foreplay” — it’s the beginning of modern music. The performance was ravishing and coolly intense, as if the dark volcanic forces of the subconscious could erupt at any moment from under the repressive but glittering surfaces of civilization.

Cataclysm itself exploded in the form of Stravinsky’s Symphony in Three Movements. You could hear the bombs falling on either side of the tender interlude for harp, oboe, and flutes (music once evidently intended for the movie The Song of Bernadette). Boulez must have been very happy, because he followed this with something I’ve never heard him do: an encore, Stravinsky’s Circus Polka, which was commissioned by George Balanchine for his dancing-baby-elephant ballet at Ringling Brothers/Barnum & Bailey. Boulez has a sly sense of humor — it was delicious to hear him in a mood of unbuttoned hilarity. The orchestra played Stravinsky’s inebriated quotations from Schubert’s famous Marche militaire with a teasing Viennese lift.

The rehearsals were really run-throughs, with some stopping to iron out knotty passages. At the next day’s rehearsal of Bruckner’s Ninth Symphony, Boulez went over and over a tiny three-note phrase at the beginning of the Scherzo, to get from the spectacular woodwinds the precise rhythmic articulation he was looking for (it was there in spades at the performance). In the Mahler Third, he got the American Boychoir to sound less like boy sopranos than like real boys imitating bells.

I was especially fascinated by Wagner’s orchestral Prelude and Liebestod from Tristan und Isolde — music, Boulez writes, “of transition rather than of retrospection and repetition.” So instead of multiple orgasmic climaxes, there was one long, evolving line that finally burst forth into playing of heartbreaking tenderness in the wordless “love-death” music.

I found both the Bruckner and the Mahler extraordinary in their dramatic urgency. For years, I’ve considered an old live performance of the Mahler Third, with the BBC Orchestra, a touchstone for great Mahler playing. These New York performances, with an orchestra for whom Mahler and Bruckner are chicken soup, were of an even higher order, with a virtuosity and understanding that exceeded even James Levine’s stunning Mahler Third with the BSO last month. (For Jeffrey Gantz’s slightly different reaction to Boulez’s Bruckner and Mahler, see the sidebar opposite.)

Boulez has an uncanny instinct for exactly what it takes for each note, each phrase, to sink in. The Mahler seemed to come not so much from the orchestra as from some place inside my own body. I was so choked up by it I could hardly speak; so transported, I actually took a subway going in the wrong direction. Do I want to hear more new pieces by composer Pierre Boulez? Of course. But do I want him to give up conducting on this level, even for a year?

AT THE BSO, the closest event to this lofty level was actually not originally scheduled. Yo-Yo Ma was supposed to play in a new piece by Tan Dun, but it wasn’t finished in time, so instead we got Richard Strauss’s Don Quixote, a Ma specialty. He was heartbreaking in the “role” of the benighted knight (whose dying breath expires in an unfinished cello glissando), and BSO principal violist Steven Ansell equaled him in the smaller but trickier role of Sancho Panza. Ozawa excels in simple narrative, and the orchestra’s impersonations (bleating sheep, menacing windmill) were beyond reproach. The evening began with John Williams’s Cello Concerto. At its 1994 premiere, at the opening of Tanglewood’s acoustically challenged Seiji Ozawa Hall, you couldn’t hear the cello. A rehearing, even with the benefit of Ma’s lavish gifts, revealed little beyond tinkling soundtrack sentimentality.

The week before, Bach’s B-minor Mass was soulless and lackadaisical (except, of course, for Ozawa’s suddenly fast, loud climaxes) — a waste of four international star vocalists, including bass Thomas Quasthoff, who at least managed to inject some verbal and emotional energy into his singing. The snow-emergency cancellation prevented my hearing the BSO debut of conductor David Robertson, who had programmed a big new piece by John Adams. (Anyone have a tape I can listen to?)

Then Haitink was back, leading the BSO (because of the snowstorm one rehearsal short of a full deck) in a program of Stravinsky’s Pulcinella Suite, Leonard Bernstein’s trashy “nocturne” Halil (with stellar BSO principal flute Jacques Zoon, who is being courted by the Berlin Philharmonic), and Brahms’s Second Symphony. With the Vienna Philharmonic still in my ears, I was dismayed by the sloppiness and squareness of what should have been scintillating Stravinsky, and by the cramped, flat texture in the Brahms (oh, for those Viennese “depths”), though Haitink built the last movement to a spirited conclusion. The BSO program booklet, with its third (and best) cover of the season, featured a thoughtful essay by Brahms biographer Jan Swafford on the darker undercurrents of what most people consider Brahms’s cheeriest symphony.

ON ASH WEDNESDAY, Benjamin Zander and the Boston Philharmonic programmed one of their most ambitious ventures, Sir Edward Elgar’s turn-of-the-century oratorio The Dream of Gerontius (Everyman as Dying Elder), whose text is Cardinal Newman’s longwinded Catholic poem. A nearly sold-out Symphony Hall suggested serious curiosity about this rarely performed work. A couple of decades ago, Colin Davis led it at the BSO with Jessye Norman singing the Angel who guides the soul of Gerontius into Purgatory. I can’t imagine a stronger advocate for it than British-born Zander. But you might have to be British to enjoy it, too. Zander regards it as Elgar’s masterpiece, but I found the music itself lacking in heart-stopping inspiration (though I recall being more moved when I listened to Benjamin Britten’s quieter, more relaxed recording).

The commitment of the playing didn’t quite carry one past the technical inadequacies the way it sometimes can in more engaging music. The best of the three soloists was 29-year-old Canadian bass-baritone John Relyea, who apparently started out as a rock singer. He has a voice of rich and resonant sonority that makes you sit up and listen. It’s hard from this piece to know how subtle a singer he might be. As the dying, then dead Gerontius, the distinguished tenor Anthony Rolfe Johnson was having a hard day. He blew a couple of important high notes (maybe he had a cold), but throughout his singing was so dry, it compromised his ability to shape a phrase. Mezzo-soprano Michelle DeYoung, six feet tall with blond curls piled on top of her head, looked as if she had a bigger, steadier, and more voluptuous voice than she actually did. Jeffrey Rink’s Chorus pro Musica sounded more convincing as one large group than when the parts were parceled out to individual sections. The Demons were especially devilish.

And in a concert devoted to music from Vienna in 1791 (Mozart’s last year), Martin Pearlman’s Boston Baroque gave the modern premiere of The Beneficent Dervish, a comic musical created by the same company that first put on Mozart’s The Magic Flute. This was a follow-up to Boston Baroque’s performance two seasons ago of The Philosopher’s Stone, a forgotten singspiel to which Mozart actually contributed. Dervish is lightweight but delightful. Mozart must have liked it because he evidently got some ideas from it. Soprano Sharon Baker, mezzo Deanne Meek, tenor John Aler, and basses Kevin Deas and Alan Ewing made an engaging ensemble; Baker, Meek, Aler, and Deas returned for the mostly-Mozart Requiem, in Robert Levin’s skillful performing version, which makes the parts Mozart didn’t complete himself sound more like Mozart. The performance fell about halfway between lukewarm and white-hot and could have used another rehearsal or two. Still, even a little real Mozart is better than none.