MUSIC REVIEW : Johnny Mathis Still Wows ‘Em : Pop: The shy, velvet-textured baritone can still sneak up from behind to caress each note individually. He remains the quintessential romantic singer.

The enigma that is Johnny Mathis alternately charmed, thrilled, and perhaps even confused a capacity audience of 1,200 at Humphrey’s on Tuesday night.

If his two-hour-plus show left one with an overriding impression, it is that time has marched around, and not over Mathis, who closes a three-night engagement at the Shelter Island venue with a single show tonight. Though he turns 56 in September, the remarkably trim, youthful vocalist looks as though he stopped aging at 35.

That suspension of time was mirrored in Mathis’ performance. The soft-toned, velvet-textured baritone, which seems to sneak up from behind to caress each note individually, remains intact. So, too, the unusually rapid

vibrato that imbues a phrase with an artless innocence. Employing these Mathis trademarks, he demonstrated the same gentle manipulation of melody and lyric that made him the quintessential romantic singer beginning with a series of hits in 1957.

Backed by his four-piece traveling band and an orchestra of local symphony musicians, Mathis opened with “99 Miles from L.A” and slipped easily into “Without Us,” his duet with Deniece Williams that became the theme song for the television sitcom, “Family Ties.” The show then reached the first of several peaks with a faithful reading of “Chances Are,” the 1957 ballad that was his first hit single.

Although Mathis has been a mainstay of the casino circuit for many years, his rendition of “Chances Are” evidenced one major difference between him and his lounge-show peers: After 30-odd years of concertizing, the notoriously shy Mathis still projects a slight nervousness onstage that precludes the slick, perfunctory manner of the typical Vegas-Tahoe crooner.

Mathis also exhibits an unflagging respect for the songs themselves, remaining untouched by the medley-mania that afflicts so many longtime stars. When he sings, Mathis moves little, seems to fix his gaze on a spot in the distance, and almost imperceptibly contorts his lithe frame as if to completely envelop himself in the lyric.

Such concentration draws the listener into The Moment, and Tuesday night it made “Chances Are” sound as fresh and bittersweet as it did when it first hit the airwaves.

His bashfulness might also explain why Mathis doesn’t engage in a lot of shmoozy banter with the audience. For the past 17 years, he’s been leaving those duties to comedienne Jeannine Burnier, and it was her intrusion into the proceedings that provided the show’s only lull. For whatever reason, Mathis prefers to have Burnier perform during, rather than before his portion of the concert. On Tuesday, he introduced her after only five songs and beat feet, creating an awkward interruption of momentum.

Due to the generally “mature” age of the audience, Burnier’s Erma Bombeck-ish material went over well. However, the comic’s somewhat predictable jokes about shopping, aging, wrinkling, sagging and whatnot provided an unfortunate, deflating counterpoint to the suggestion of timelessness in Mathis’ repertoire. When a 15-minute intermission was announced following Burnier’s lengthy spot, there were more than a few puzzled looks in the crowd.

Any fears that ticket holders might not get their $34 worth of Mathis were quelled by a generous second half that opened with the Erroll Garner ballad, “Misty.” Everyone with a voice has sung this chestnut, but Mathis’ 1959 recording remains the model. In his performance at Humphrey’s, the singer met his own high standards, even nailing his recording’s now-famous, mid-song high note, which elicited a loud ovation.

Mathis did well-received covers of such radio hits as the Four Tops’ “Ain’t No Woman Like the One I’ve Got” and the James Ingram-Patti Austin ballad, “How Do You Keep the Music Playing?” He also drew a hearty response with Duke Ellington’s “Don’t Get Around Much Anymore” and a Brazilian medley that included a lovely translation of Dori Caymmi’s “Photograph.” But a suite of tunes from “West Side Story”--including a hushed “Maria” and climaxed by a gooseflesh-raising version of “Somewhere”--pulled many in the audience to their feet.

Perhaps the most poignant moments in the concert came during a segment in which Mathis was accompanied on Spanish guitar by longtime associate Gil Reigers. A beautiful reading of the Stylistics’ “Stop, Look, and Listen to Your Heart” was surpassed only by an almost excruciatingly delicate version of Mathis’ 1957 hit, “The Twelfth of Never” that tugged at the tear ducts.

If anyone left Humphrey’s feeling disappointed, it wasn’t due to what was in the show but what was left out. Such Mathis oldies as “It’s Not for Me to Say,” “Wonderful! Wonderful!,” “Small World,” “When Sunny Gets Blue” and “What Will My Mary Say” were nowhere to be heard.

But it’s a tribute both to the man’s talent and to the giving nature of his performance that even mentioning such omissions seems like quibbling.

Johnny Mathis ends his three-night engagement at Humphrey’s tonight with one 8 o’clock show. At press time, there were still some seats left.