"The Jazz Singer" is not an antique that cried out to be dusted off and placed on prominent display. The remake now at area theaters is such a half-baked, arbitrary update that the decrepit plot seems to arise from the misty region of a kind of Jewish Brigadoon in contemporary Manhattan, a Ghetto That Time Forgot.

The filmmakers are stuck rather ludircrously in a time warp. But then if they were in sufficient touch with reality, they wouldn't insist on the obviously outdated title for a movie desinged to gloridy Neil Diamond -- who may be considered a singer by current loose standards but would not be described as a "jazz singer" by his most sarcastic enemy.

The original 1927 production was a silent weepie unexpectedly transformed by Al Jolson's recorded interludes of singing and ad-libbing, which electrified audiences and revolutionized the movie business. The plot about a cantor's son who alienates his devout, orthodox papa by pursuing a show-business career and remains estranged until papa hovers at death's door on Yom Kippur was regarded as a rather embarrassing bathetic excess at the time.

Remade in the early '50s with Danny Thomas, "The Jazz Singer" attracted no following at all. So why a newly misbegotten, preposterously diverting remake? Not because anyone thought that "The Jazz Singer" was an irresistibly fresh, exciting concept for a movie. It was produced because Diamond, an awesomely blah incarnation of the rebellious boy with pop music in his soul, Jess Robin (ne Yussel Rabinovitch), already enjoyed a following that would presumably guarantee big sales for an accompanying record album.

This approach is one of the curses of modern moviemaking, but it may indeed prove commercially sound. If there's any justice, the finished product will terminate Diamond's career as a film star in its faint, drowsy tracks and advance the career of Lucie Arnaz, cast as a record publicist who becomes his first booster and second missus.

Arnaz has to do the acting for both of them, and she almost manages to take the edge off Diamond's formidable drabness, which makes you think of a lobotomized Ben Gazzara.

Arnaz's big saucer eyes, which encase mischievously mobile dark eyeballs, are wonderful expressive instruments, and she takes such radiant, overcompensating pleasure in Diamond's scratchy, droning vocalizing and glum, droopy presence that you can't help wishing her well. She doesn't even scold him for going off in an egotistic pet for months and leaving her alone to bear their firstborn son (named Charlie Parker Rabinovitch, apparently by the hero's devoted black buddy, Bubba, played by Franklin Ajaye, who remains behind and seems privy to many intimate details about Mrs. R. ignored by her self-centered, absent-minded spouse). By God, Lucie Arnaz earns the chance at a real leading man or a movie of her very own sometime soon.

This version, directed by Richard Fleischer, discards the hero's dear old mama (not a bad idea) but retains the old-fashioned papa, now impersonated by Laurance Olivier, still belaboring his sorrowful Old Codger From The Old World routine, which looked shamefully terminal in "A Little Romance." Howeverm he is far more restrained than Warner Oland in the Jolson version, and some of the burden of being a stick-in-mud is shared by a blissfully unworldly new character, Catlin Adams, as the hero's first wife, so content in her role as a poor assistant cantor's helpmate that she can't imagine anything more exciting and gets left behind when show biz beckons.

Although Diamond has no credentials as a movie performer, the production defers to his status as a recording star, even in ways that defy common sense. Bubba persuades Robin to pass for black at an audition at a Harlem club when one member of Bubba's group, The Four Brothers, gets arrested. Although one member of the audience ultimately shouts "That ain't no brother!" and provokes a melee, the wonder is that no one throws the group out when it begins performing. We're really supposed to believe that Diamond going "Oooo-eeee, baby!" repeatedly in his inimitably paleface style would drive black patrons into delirious swingin' and swayin'.

The same delusion carries over to a concert appearance before a supposedly rowdy audience in L.A. and a Country & Western bar in the Southwest, where Diamond's grotesque arrangement of "You Are My sunshine" would almost certainly earn him a well-deserved roost on Boot Hill.

Over the past 10 years or so the domain of pop music has become an uncharted and largely unappealing wilderness to me, so I'm not sure where Diamond's constitutency is located. Maybe there's a mysterious appeal in lyrical globules like "I'll sing my songs of life . . . that I may hold you . . . inside forever . . . that you may know . . . that I'll be yours . . . and you'll be mine . . ." But I'll be damned if I can appreciate it.