Pianist Marcus Roberts is to appear at Blues Alley Monday through Wednesday. The dates were incorrect in Weekend yesterday. (Published 5/26/90)

"BLUES IS CENTRAL to American music," says pianist Marcus Roberts, explaining over the phone from Bern, Switzerland, how his new album "Deep in the Shed" became a blues prism. On tour with trumpeter, mentor and "best friend" Wynton Marsalis, the 26-year-old pianist's voice is humming with static.

"If you're not dealing with a certain level of blues feeling when you play, if you're not dealing with the architecture, the form of blues, you're missing something central to the music," he says. "That's what made me want to play all these blues in different keys and create different moods."

Six blues covering 12 keys, in fact, if you count the modulations. Sultry, earthy, joyous, exotic, playful, anguished blues, richly orchestrated blues that will be reprised when Roberts and his young band open a three-night stand at Blues Alley Monday.

"It took me quite a while, a few months to get all the music together," Roberts adds. "Even on my first record {1988's widely acclaimed "The Truth Is Spoken Here"}, I was trying to lay out conceptually the range of things I would like to do in my career, as far as my approach to the instrument goes. I had the architecture of the {new} album in mind before all the pieces were written, so eventually I had to write pieces that would convey all the moods I want to capture."

The title "Deep in the Shed," reflects the strong emphasis Roberts places on study and practice -- in jazz parlance, "woodshedding."

"You have to practice," he insists, "but not just on generic technique -- that's the lowest level. I'm talking about learning the art of improvisation, learning how to listen, analyzing from a historical perspective what your instrument's place in the music is.

"Also, when I'm talking about shedding, I'm talking about finding a balance between your life as a musician and . . . as someone who can contribute something that's useful to other people -- having more than just a personal agenda in mind."

If Roberts's philosophy on life and music seems in line with the one often expressed by the more outspoken Marsalis, it's hardly a coincidence. Roberts quickly acknowledges the trumpeter's pervasive influence.

"My experience of working with him over the past five years has been the most musically provocative one of my life," he says. "The range of material that we play and the range of conceptual ideas he has as an artist and a person is tremendous."

Nor is it a coincidence that Marsalis recently recorded his own blues portrait, "Majesty of the Blues."

"Of course, we share interests and influence each other," Roberts notes, "so when he recorded 'Majesty of the Blues,' it got me to thinking about doing an album of all blues."

(As for the rumor that Marsalis actually performs on "Shed," under the pseudonym "E. Dankworth," Roberts won't confirm or deny.)

Blind since the age of 4, Roberts was born in Jacksonville, Fla., and began formal piano just as he was about to enter his teens. He studied classical piano for nearly a decade but soon discovered his affinity for jazz was stronger. Plus the workload didn't appear quite as daunting.

"When I go into a record store," he says, laughing, "and I see people who've put out the complete works of Beethoven -- phew! I'm not prepared to do all that work."

A lot of Washingtonians first became acquainted with Roberts when he won the first Thelonious Monk International Jazz Competition in 1987, walking away with $10,000 in prize money and high marks from a discerning jury of jazz pianists.

"If you win a competition, it's not going to be a singular achievement that will make you a great musician," Roberts asserts. "You have to look at a competition as a means of getting you to reach deeper within yourself to try to reach another stage of development as an artist. To me it was very important, because it made me realize how great a genius Monk actually was."