Like Alec Wilder, composer and arbiter of popular and formal music, a ""man of Johnsonian principles and persuasions,"" who is accorded a disciplined reverence by Balliett in a final chapter, the author is drawn to ""the jazz musician's bittersweet, witty, lonely world."" In monograph/ interviews with a handful of committed craftsmen, not all well-known except by peers, Balliett follows them up into some rarefied heights. There's pianist Marian McPartland: ""Swinging. . .is like a souffle; it rises and rises and rises. But it's dangerous. . . ."" Or Wilder on Tony Bennett: ""Pinza inflated Rodgers' songs, but Bennett illuminates and aerates them. . . ."" And so on through in situ appreciations of Mabel Mercer, Bennett, Blossom Dearie, Bobby Hackett, Ruby Braff, McPartland and Marie Marcus. Plus the inclusion, not surprisingly, of another craft, represented by the comic precision of Bob and Ray. Wilder has observed of horn player Braff ""every note he plays is the center of that note,"" and this is, in a sense, the value of Balliett's perceptions of the music -- sung, played or verbal -- he hears. His critical statements are devoid of doctrinaire overlay and attuned to the nuances of craft. In the chaste quiet of Balliett's listening room, even such flights as ""there are deep register phrases that suggest wine cellars"" or ""Irish sweater (texture)"" seem exactly straight and center. An attractive tribute to that small aristocracy of performers.