Nowhere is the resurgence of rhythm and blues more evident than in the ascendance of the new-and-improved slow jam. These ballads and mid-tempo laments, long a staple of adult-directed “quiet storm” radio formats, have been the upscale, “soft” antithesis of hip hop’s hard knocks. But lately they’ve undergone urban renewal. A little over two years ago producers like Sean “Puff Daddy” Combs began taking R & B songs and infusing them with hip hop beats and gruff attitude to create a stronger, street-smart style. Mary J. Blige’s “Real Love”–a combination of frenetic beats and impassioned singing–typified the style, which has come to rule the charts.

The rise of this slow jam has led to a proliferation of male vocal groups such as Boyz II Men, Shai, Silk, and Jodeci–and a variety of distaff counterparts, like SWV, Jade, and Blackgirl–many of whom have gold or platinum discs to show for their efforts. But, as is often the case, the artistic accomplishment of these groups–particularly the guy groups–has lagged well behind their commercial success. The requisite “hardness” is often just a pose, but it’s hard to abandon. And the slow jams these groups have ridden to fame and fortune require a vulnerability that has not been on the usual pull-down menus of contemporary black masculinity. Without it a lot of the songs in this subgenre are loaded with empty gestures: at best they’re beggin’ for bootie when they mean to be beggin’ for love. When they should be putting their heart and soul on the line, these singers are trying to impress the girls with their machismo and good intentions. We don’t need Shere Hite to tell us that most women are going to find that pitch really tiresome.

This is regrettable, because the slow jam has a distinguished history: consider Otis Redding’s “Try a Little Tenderness,” Smokey Robinson’s “Tracks of My Tears,” Barry White’s “Can’t Get Enough of Your Love, Babe,” Earth, Wind and Fire’s “Reasons,” and Luther Vandross’s “Here and Now.” But love is a man’s job, and these nouveau jack loveboys offer little more than playground fantasies.

Things got off track with Luther Campbell’s Miami vice; 2 Live Crew’s “Me So Horny” has started a sort of b-boy-at-the-Admiral-Theatre school with ribald offspring like Wreckx-N-Effect’s “Rump Shaker,” Hammer’s “Pumps and a Bump,” and Sir Mix-A-Lot’s “Put ‘Em on the Glass.” By comparison almost any indication that a woman just might be more than the sum of her genitals isn’t just refreshing, it’s cause for celebration.

On 12-Play R. Kelly takes a reasonable shot at adding to the canon but falls short. He’s a gifted singer with a magnificent physique–one of the few men on the planet who could watch Salt-N-Pepa’s “Shoop” video without the vaguest pang of insecurity–and he’s worked these attributes to triple-platinum status. On the album’s second single, “Bump n’ Grind,” which caught everyone but Kelly off guard by becoming one of the biggest R & B hits of all time, he sings mostly about lust; his idea of subtlety is anguished longing, and he cradles his earthy melismata in soft, billowy backgrounds. It’s as if he sought to combine the tormented craving of Marvin Gaye’s “Let’s Get It On” with the sultry cool of Sade’s “Nothing Can Come Between Us.” But this attractive synthesis lacks the solid songwriting of its predecessors; its success is economic, not artistic. Fewer than half the tracks on 12-Play sustain any semblance of narrative flow or musical development. Like the third single, “Your Body’s Callin’,” the tracks are riffs and vamps for Kelly to moan and groan over. Satin sheets are a start, but they do not create a sensuous environment, something Kelly evidently has yet to learn. Maybe sometime in between shooting a pinup calendar and remixing the sixth single from the recording he’ll get it.

Keith Sweat got it from the start. Since his 1987 debut, Make It Last Forever, the former Wall Street stockbroker (go figure) has been a pivotal figure in black popular music. His first hit, “I Want Her,” was one of Teddy Riley’s first great new jack swing singles and one of the best records of the decade. Yet Sweat was much more than a Riley dance-pop acolyte. He sang with depth and sincerity and smartly added elements of street attitude to his finely appointed ballads. And he was one of the few artists to take it to the stage with the same aplomb he displayed on record. He spent much of the late 80s and early 90s touring relentlessly. On his second and third records–I’ll Give All My Love to You, from 1990, and Keep It Comin’, from ’91–Sweat refined his role as street-smart lover man. He abandoned the up-tempo material and for many became Luther without the affluent baggage. His recent Get Up on It moves his music just a bit farther toward the kind of street R & B hybrid that his music prefigures. TLC’s Left Eye, who recently hit the tabloids for allegedly burning down her boyfriend’s mansion, raps on two versions of “How Do You Like It?” and Roger Troutman of Zapp fame duets on “Put Your Lovin’ Through the Test.” Overall the beats are more insistent, and Sweat’s gritty tenor is as affecting as ever. Yet it all seems just a little too pat. Sweat long ago solidified his position as the premier Romeo in pop music. Now he should take some risks: do an up-tempo dance tune or a jazzy duet. Get Up on It is meticulously crafted, but a sense of sameness sets in after a few listens.

I’m not sure that Sweat’s core audience, which is almost entirely female, minds much though. There aren’t many men in music or out who articulate their emotions as well as Sweat does. It’s interesting to note that women relate to Toni Braxton singing “You Mean the World to Me” or En Vogue doing “Giving Him Something He Can Feel,” but the flip side doesn’t play. Guys don’t dig Sweat or Kelly. When confronted with the prospect of relating to the yearning sensitivity of a Sweat or a Vandross, men often respond with some variation on a Calvin-ish “Yuck. Mushy girls’ stuff.” The situation suggests that while the nouveau jacks have some growing up to do, they are far from alone.