* 1/2, KEVIN MAHOGANY, “Kevin Mahogany,” Warner Bros.; ** ALLAN HARRIS, “Here ComesAllan Harris . . .,” Mons

What’s the problem with jazz singing in the ‘90s? Certainly not the music, which seems to be improving both in quality and quantity. Nor is there any absence of emerging talent, as these new recordings make amply clear.

The problem is more a perennial one, the question of definition--the never-conclusively designated line between jazz and pop singing--with its ancillary question of the extent to which commercial interests should affect a jazz vocal recording.

Almost universally praised as one of the most gifted new jazz voices of the ‘90s, Mahogany makes his major-label debut not with a strong jazz program but with a production that verges far closer to rhythm and blues.

Nothing necessarily wrong with that. Joe Williams, one of the two or three finest jazz singers in the world, was first known as a blues singer--as was Billy Eckstine. In Mahogany’s case, however, the music on the album has the distinct quality of having been driven by marketing rather than musical decisions.

Obviously, there are commercial benefits to increasing his visibility (and sales) with R&B; and adult contemporary audiences. But it’s hard to avoid the feeling that the burgeoning jazz journey of a potentially important artist has been sidetracked somewhat by a recording that fails to reveal the full range of his skills.

To his credit, Mahogany, who opens a five-night run at the Jazz Bakery in Culver City on Wednesday, sings with ebullient enthusiasm, displaying impressive soul-drenched phrasing in tunes such as “I Love You More Than You’ll Ever Know” (originally recorded by Blood, Sweat & Tears), Gamble and Huff’s “Yesterday I Had the Blues” and the old Fats Domino hit “I’m Walkin’.”

He is backed by a band that features Larry Goldings on organ, Peter Bernstein on guitar and Kirk Whalum on tenor saxophone--all players with the capacity to deliver the inflections of jazz to R&B.; But, although Mahogany produces some effective scat singing here and there, only on Stevie Wonder’s “I Never Dreamed You’d Leave in Summer” and the Barry Manilow-Johnny Mercer ballad “When October Goes” do his subtle jazz qualities begin to materialize.

The lesser-known Harris has a considerably more compelling setting, singing with an orchestral accompaniment that few younger jazz vocalists have ever had the opportunity to experience. Performing a program of standards with the 54-piece Netherlands’ Metropole Orchestra, Harris is harmonically embraced and rhythmically propelled by a group of stunning large jazz ensemble arrangements written by the redoubtable Rob Pronk.

Harris is a pleasant singer, his voice resonating with the sound and style of Nat “King” Cole. But at this moment, at least, he has neither the versatility nor the musical presence of Mahogany. Yet Harris’ recording is the one that appears to have been made with sheer musical expressiveness as its first consideration.

Which brings us back to the problems of definition and commercialism. The Harris album provides (with funding from the Netherlands’ NPS Radio) the kind of rich accompaniments that were routinely produced for, say, Ella Fitzgerald and Billie Holiday, while Mahogany--the superior talent--is squeezed into a market-oriented crossover package.

Listening to the two albums, one can only wonder what sort of magic Mahogany might have generated if he had been the performer singing with the superb Pronk orchestrations. Maybe next time.

*

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