There are also, of course, echoes of ''Thriller.'' A melody line from ''Billie Jean'' reappears in ''Liberian Girl,'' while ''Dirty Diana,'' a song about a groupie who latches onto the narrator, mixes the sexual fears of ''Billie Jean'' with the hard-rock lead guitar of ''Beat It.'' The low-slung riff in ''Bad'' recalls the one from the song ''Thriller.'' And where Paul McCartney and Mr. Jackson argued over a romance in ''The Girl Is Mine'' on ''Thriller,'' on ''Bad'' Stevie Wonder and Mr. Jackson do the same in ''Just Good Friends.''

For the first time, Mr. Jackson has written most of the songs for an album - 8 of the 10 songs on the ''Bad'' LP and cassette, 9 of 11 on the compact disk. (He wrote four out of nine songs on ''Thriller.'') But ''Bad'' is an even less revealing album.

Mr. Jackson's lyrics on ''Thriller'' testified to overwhelming fear and paranoia; ''They're out to get you, better leave while you can,'' he warned in ''Beat It.'' On ''Bad,'' there are still a few signs of that fearfulness. ''Dirty Diana'' reduces the singer to a terrified whimper; in ''Smooth Criminal,'' the singer finds a bloodstained carpet and an unconscious body, and asks, obsessively, ''Annie are you O.K.?'' when, clearly, she's not. But Mr. Jackson generally stays away from psychological danger zones. He portrays himself in conventional pop terms, as a lover and as a rather tame outlaw; when he insists he's ''really, really bad'' in ''Bad,'' he's not too believable.

Beyond those poses, he seems isolated and glad of it. ''Man in the Mirror,'' written by Siedah Garrett and Glen Ballard, declares that the way to ''make the world a better place'' is to ''take a look at yourself and then make that change''; it's activism for hermits. The compact disk of ''Bad'' has an extra, closing song with an unmistakable message: ''Leave Me Alone.'' The oddest lyrics show up in ''Another Part of Me,'' cosmic tidings delivered by a messianic ''we.''

While the lyrics on ''Bad'' are largely impersonal, the music revolves around Mr. Jackson's singular voice. He has taken his vocal mannerisms even further - the intakes of breath, the hesitations, the whoops -and they add up to lead singing that finds percussion in every consonant and cross rhythms with every ''hoo hoo!'' and ''aaow!'' Although Mr. Jackson will never be a shouter, he can summon timbres from a soul singer's raspy exhortations to his androgynous alto.