Nobody's weeping over the lack of a psychobilly Sgt. Pepper. If the wedding of Sun Studios' bop circa 1956 and the loud-fast credo of punk happened in a vault shut to evolution, who cares? No other genre supplies quite the sicko wit, raging guitars, and redolent bad taste. Even those masterful Cramps never truly outdid their debut; nearly 20 years on, Lux and Ivy's musings feel dangerously contrived and shticky. Relative, that is, to the slapdash sloppiness of newer sprouts such as Reverend Horton Heat, a trio led by Eastern Texas Juvenile Correction Facility graduate Jim Heath (alias the Reverend Horton Heat) who've just released their fourth disc, It's Martini Time (Interscope).

Heat assured one interviewer that Martini Time differs from anything the band have done -- but don't believe it. Appearances by horns, piano, accordion steel guitar, and sound loops don't hide the truth: the Reverend Horton Heat band are on this Earth to play 200-mile-a-minute mutant hillbilly, and to promote good, unclean living in the process. (Red meat, pot, souped-up cars, and malt liquor are sacraments in the Church of the Reverend Heat.) Innovation is not the name of this game, even if Martini Time does feature the Reverend's first spoken-word cocktail-jazz number, "That's Showbiz."

Not that Horton Heat have been wild-eyed psychobillies forever. As a baby band, back in 1987, they had more purist intentions. Then they toured pretty much nonstop for a good four years. By the time they got around to spending time in the recording studio, the trio didn't sound much like anything Sam Phillips ever cooked up back in Memphis. So there has been a certain degree of (d)evolution.

Since their 1991 debut, Smoke 'Em If You Got 'Em (Sub Pop), the best Horton Heat songs have been those that inch toward novelty but get saved by sheer dint of spirit and a solid backbeat. (When the "psycho" doesn't wipe out the "billy," that is.) Unlike the Cramps, who at this point pile on the perversity as a matter of routine, the Horton Heat haven't lost their ability to be funny without straining. Maybe that's because their weirdo amusements aren't too tilted from reality. "Come on down, see the big dwarf rodeo," Heath crooned on one particularly inviting number from Smoke 'Em. Now, there was some sort of hoo-hah about Australian dwarf-tossing tournaments in the news back then; from tossing to wrangling is not too great a distance. There you have it: the band have been going around sneaking in subliminal messages about Australian society's mistreatment of small people.

Or maybe not. Anyway, the band'll do that to you. Heath's the sort of guy who warbles one thing and means another. Like when he had that big pink pig that needed nurturing on The Full Custom Gospel Sounds Of . . . (Sub Pop). Or when he's offering his babe a ride in his "Big Red Rocket of Love," or when he's proposing a solution to the dilemma of having a "Crooked Cigarette" on Martini Time.

Meditations on impurity of the mind and body have always been Heath's sweetest gift. Thus it was a little disappointing when the band's previous release, Liquor in the Front (Interscope), didn't live up to its titular vulgarity. (The unabbreviated title included ". . . Poker in the Rear.") Even with famed madman Al Jourgensen manning the production board (and burping and stuffing pencils up his butt on cue), Liquor's debauchery was muted. That problem has been addressed on the new disc, which reeks of indecency despite normal-guy Thom Panunzio's producing (U2, John Lennon, Rocket from the Crypt).

There's "Slow," a metaphorical ode to getting home faster by driving slower and keeping a cool head, and "Red Rocket." Both manage not to sink to noisefest monotony the way Horton Heat often do when things get really speedy. Unfortunately, a lot of Martini Time does suffer that velocity-driven blandness, even if Heath's yarns are worth a good chortle. "Generation Why," which offers more of that topical Reverend Heat cultural criticism, is whiny and wearisome. "Now, Right Now," a pounding harangue about not getting laid on demand, and "Spell on Me," a fast ramble that doesn't distinguish itself, are a little annoying.

Martini Time works best when it either sticks to old-time basics ("Rock the Joint" is a blast) or gets deliciously ridiculous, as on "Cowboy Love," a rustic swing through interracial homosexual rapture. This one may get the band lynched if they play it in the wrong whiskey joint. But that's a risk you take when you're aiming for radical new frontiers in the psychobilly genre. Hah.