The poor sound wasn't the only problem with Bob Dylan's recent concert in Washington. A far more fundamental problem was the preachiness and humorlessness of Dylan's recent music.

Now you might think that the man who popularized protest lyrics in the '60s has always been a bit preachy. But if you go back and listen to those early songs, you'll find that Dylan was no smug sermonizer prescribing the one true path. Instead, he was more the iconoclastic prophet who delivered his warnings with a take-it-or-leave-it attitude.

He underlined that attitude with an irreverent wit that often made his songs hilarious. That humor began to fade with the "family" albums, from "Nashville Skyline" onward, and was largely replaced by a smug righteousness after he got religion.

Though Dylan himself has seemingly forgotten his old wit and irreverence, the musicians who admire him most haven't, and they draw it out whenever they collaborate with their old hero. They succeed on about half the songs on Dylan's new album, "Knocked Out Loaded" (Columbia, OC 40439). One of those songs, "Brownsville Girl," is the best thing Dylan has done in 11 years.

Sam Shepard, the Pulitzer Prize-winning playwright who wrote a book about his adventures on Dylan's 1975-76 Rolling Thunder tour, wrote "Brownsville Girl" with Dylan. Shepard's plays of the '80s boast the same surrealistic twist on American mythology that Dylan's mid-'60s songs had. "Brownsville Girl" sounds unmistakably like a Shepard monologue stretched out over 11 minutes of lazy country-folk-rock. It's both funny and unpredictable.

Sounding uncannily like Willie Nelson, Dylan sings in a bemused voice over the dawdling Texas shuffle. He recalls a childhood memory, the climactic scene of Gregory Peck's 1950 film "Gunfighter," but in Shepard monologues, memory soon proves untrustworthy. In much the same way, the singer recalls his ex-lover, the Brownsville girl, but finds his shifting memories hard to pin down.

As the singer drives through the Southwest with a new lover, he finds the old gunfighter myths replaced by unemployment and a corruption that affects "even the swap meets." As he visits his old haunts, the singer can't decide whether he's chasing memories or fleeing them. In the end, he imagines himself in an old cowboy movie fleeing a posse, and when the Brownsville girl saves his life he realizes she's only acting.

The bright, bouncy chorus, backed up by Mexican horns, sounds sincere at first, but ends up sounding quite ironic. Even Dylan's gospel choir, which sings solemnly throughout the rest of the album, mocks him with cat screeches and an "oh yeah?"

Another Dylan admirer, Tom Petty, cowrote "Got My Mind Made Up," which also boasts a late-'60s looseness. With Mike Campbell recreating Mike Bloomfield's slide guitar fills, the song rattles and rolls like an outtake from Dylan's 1965 album, "Highway 61 Revisited." Dylan himself sings with a refreshingly brash indifference to what anyone else thinks: "If you don't want to see me, look the other way."

Side 1 begins with two inspired cover songs. "You Wanna Ramble," by Junior Parker (the Memphis bluesman who wrote "Mystery Train") is given a late-night roadhouse treatment by Dylan, guitarist T-Bone Burnett, pianist Al Kooper and bassist James Jamerson Jr.

Kris Kristofferson's "They Killed Him" is a tribute to such martyrs of conscience as Gandhi, Martin Luther King Jr. and Jesus Christ. Kristofferson's sophisticated variation on "Abraham, Martin and John" gets the same powerful hymn-march treatment that Dylan gave his own eulogy for "Lenny Bruce."

The rest of the album is much less successful. The third collaboration finds Dylan paired with one of the worst songwriters in America, Carole Bayer Sager, and the drippy ballad that results reflects that. "Driftin' Too Far From the Shore" and "Maybe Someday" showcase Dylan at his preachy worst. His country arrangement of the gospel standard "Precious Memories" proves rather pedestrian.

"Knocked Out Loaded" seems to have been assembled from many different sessions over the past year. The only musical constant is Dylan and his gospel choir, the Queens of Rhythm. The playing is always loose and lively, but when Dylan gets preachy the music can be as unsubtle as a sledgehammer.

"Peter Case" (Geffen, GHS 24105), the debut solo album by the former leader of the Plimsouls, is an engaging album in the classic Dylanesque folk-rock style. When he opened for Jackson Browne this summer, Case played his original songs as a solo acoustic guitarist; but on the record, producers T-Bone Burnett and Mitchell Froom have framed Case's voice, guitar and harmonica with a restrained rhythm section and keyboards.

Case's songs, many written with Burnett, combine Dylan's quirky protest numbers with folky fables in a style of Burnett or Robert Hunter. Case has the good sense not to explain too much. His tale of "Three Days Straight" in a collapsed mine only obliquely suggests a fallout shelter; an ominous, unresolved mystery hangs over his story of two lovers who took a "Walk in the Woods" and never came back.

When Case writes about the lost days of youth, he has the welcome imagination to do it as an animal allegory, "Horse & Crow." His story-song about the Plimsouls, "Steel Strings," zeroes in on the nonsense surrounding the rock business. Instead of putting up with such nonsense any longer, Case has released this stubbornly uncommercial album, which finally establishes his artistic credibility.