Al Jarreau at 4: shiny-faced and self-conscious, one hand shelved on his hip like a Napoleon doll. He wears a navy blue sailor suit with long pants, the drop-front buttoned up on each side and the big bib back collar smart with red stripes and white stars. The bank of his puffy sailor's beret is very snug across his forehead. He is Master Alwin Jarreau, fund-raising for his church with songs like "Yes, I'm on the Battlefield for My Lord" and "Jesus Wants Me for a Sunbeam."

Al Jarreau today at 38: a street-strutter's gait, weighted at the spine and curving in at the shoulders. He wears a gray tweedy newsboy cap (now called, he says, a Big Apple hat), a six-foot white cashmere scarf and a leather jacket knitted at the waist. As he rolls into the parking lot behind WHUR-FM, a holstered guard swings open the back door and intones, "Do-wah, take five." His imitation of a Jarreau imitation.

"hey, that must be Al Jarreau up there!" laughs the real thing, and the show is on. Al Jarreau, the Jazz Singer, the Milwaukee kid who does Yiddeshe mama accents and Pips finger-snaps, is safe amidst his fans and feelin' "Aww, great."

Washington is a hot town for Jarreau, the jazz vocalist who scats, hums, buzzes, rolls and arpeggios like an orchestra. His Tuesday night Constitution Hall concert is his sixth or seventh D.C. date in three years. He gets "good radio support" here, according to his Warner Bros. travelling companion, Ellen Darst. He is recognized on the street; a bearded fan jerks his car to a stop in the middle of traffic to ask for Jarreau's autograph on his cassette of the new "All Fly Home" Album, high in the jazz top 10. Hearing his voice on the radio, a Howard University student hurries over armed with an absurdly long 300 mm lens to take his picture-pore by pore.

At WHUR for his fourth on-air interview Jarreau is greeted affectionately as "man" by everyone in the hall.He kisses deejay Robin Holden hello; they joke about his "rockin' out" at a party over the weekend. His fans call to ask where to meet him, how to emulate him, what his birth sign is. One says only, "Tell Al Michelle said hello."

Life is more down-to-earth at the Watergate Hotel, hostelry to the biggies, where the box of complimentary champagne is addressed to "Mr. Al Jerrreau" and he washes his shirts in Woolite. An upright steam iron oversees a half-empty glass of orange juice and nibbled toast. The bed is made up, although the maid hasn't been in yet; Jerreau is in his sock feet.

He is a crazy man in the mornings. He jEvil Eye Fleegles across the carpet, reliving the nights his a capella quartet shoo-wopped on the sidewalk. He schticks about his way of life: "So, ya vanta be a singa, huh? Getta job, ya bum!" He accompanies himself even when he's offstage, clapping when he speaks of applause and rubbering his face into the characters of his past.

Above all, he is unfazed-by his growing popularity or even the threat of losing it. In a field where album sales of 100,000 are coveted instead of the millions pulled in routinely by rock groups, Jarreau is a believer,a disciple. And if the bottom fell out of the market, he says, he'd go back tomorrow to the Bla Bla Cafe in Los Angeles and Gatsby's in Sausalito and "Do what I want the way I want to."

"that meets my criteria...I think black people are looking for someone to say something more to them than 'Boom-sha-ca-ta-da-ta-da-ta.' They're looking for music that speaks to the head as well as the heart," or the hip.

Perhaps he holds so tightly to his music because it lay on the back burner for so long, simmering in his mind, sniffed at and tasted but never served. It was his "love," his "hobby," but it was strictly funtime, weekend gigs with dance bands and high school friends.

"Only in fantasies did I think of myself as a professional singer. I had to get a pra-a-a-ctical education so I could get a pra-a-actical job. It was this vast superego thing, like Freud says.

You know, the black family, post-Sectnd World War, upward mobily bound-'Get yourself an education, boy, a profession, something you can depend on!' And they didn't even have to tell me that-maybe that's the saddest part about it, they didn't even have to tell me. It was all around; I just internalized it."

It was 1956, Jarreau was 16. The music industry had just discovered Elvis Presley. The term "race music" heedlessly enveloped everything from rock 'n' roll to backroom blues. "You could maybe count on two people's hands the number of really successful recording artists of pop music-Nat Cole, Frankie Laine, Patti Page." Becoming a professional singer wasn't a goal Jarreau conceived of; it was new, rare, an anomaly to be dreamed of and outgrown. Jarreau followed the reules, eventually getting a master's in psychology and specializing in rehabilitation counseling.

"But I'm not sad for that," he says now, his voice dropping. "I was thankful to know there was something available to me besides the foundry."

The foundry-symbol of all unskilled, cheap and exhausting labor in Milwaukee-left its imprint on the Jarreaus. Al's father, a seminary-trained Seventh-day Adventist preacher, "had a falling-out with the church" and was forced to go to work as a welder. "Not that there's something wrong about that, or about welding," he says, even more softly. "There are just...other things, if you have a choice."

Jarreau finally made his choice in 1968, disillusioned with the "official-dom" of the state of California where he worked as a counselor, singing in clubs at night.

It took seven years of clubs in Los Angeles, then New York, then Los Angeles, then New York, then Los Angeles again-as a jazz duo, a rock-jazz fusion band, then a duo again-before a Troubador engagement, opening for Les McCann, won him a contract with Warner Bros.

At long last, as he says, he's "enjoying a pretty lively little carrer in music." He's been named the No. 1 jazz vocalist by both Cashbox ('76) and Record World (78). He was last year's Grammy winner for male jazz vocalist.

And he can still sing, in a wistful, little-boy voice, the oldest song in his repertoire.

"Jee-zus wants me for a sunnn-beam ..." but the unannounced entry of a housemaid breaks off his clowning. He stares reflectively at her apologetic retreat.

"I've always wanted to be just standing there naked in my raincoat when she walks in." He twists up his mouth, throws open an imaginary raincoat and wails out a raunchy, knowing, bluesy "Na-ked!"