BACK WHEN Jerry Jeff Walker started playing at bars and nightclubs in Austin, Texas, country music was a lot different from what it is now. Back then, Willie Nelson and Waylon Jennings were still putting grease in their hair and blending into the multitude of singers in Nashville, Rusty Weir was grinding out acid rock, and David Allen Coe was in prison. Nobody, least of all Jerry Jeff, would have guessed that he was starting a musical movement of sorts, still less that all those people would be drawn into it.

After all, he was a scruffy kid whose only claim to fame was one hit single, "Mr. Bojangles," and that several years before. His voice wasn't much, kind of scratchy and whiney and not very melodic, and the only reason he got any attention at all in Austin was that the competition was so sparse. Besides, his music was sort of eclectic--maybe some would say incoherent--and it didn't really fit into any category. It wasn't exactly country, but it wasn't folk, and it was a long way from rock.

Well, things have changed a lot since then. Now that kind of music is known as "progressive country," and the people who put it out are among the best-selling artists in popular music--people like Nelson and Jennings, not to mention Emmylou Harris, Michael Murphy, and B.W. Stevenson. Nashville has faded in importance, and Austin is one of the busiest country music centers around, the home of several stars, and the owner of a sound all its own. Longhairs who used to wear peace medallions and listen to Jimi Hendrix and Eric Clapton now wear Wranglers, cowboy boots and Stetsons and spend their Saturday nights at Armadillo World Headquarters, drinking Lone Star beer, rubbing elbows with the rednecks, and carousing to the strains of steel guitars and songs about truck driving and faithless wives and husbands. The hordes at Woodstock are only a misty memory now, but every year thousands still gather in the suffocating Texas heat for Willie Nelson's Fourth of July Picnic at Dripping Springs.

The man most responsible for creating this monster is Jerry Jeff Walker, though God knows he probably didn't mean to. He's also changed a lot since then. He's no longer the grubby, lean desperado, looking like he'd like to hop the next train to Juarez. He's had a couple of successful albums, as many playing dates as he wants--even in places as distant and mysterious as Cambridge, Massachusetts--and everyone in the country music industry knows who he is. If he gets less attention than some of the latecomers, he still gets a lot, especially back home, and if the attention isn't adequate to his desires, the money probably is. He looks like a comfortable member of the bourgeoisie, outwardly indistinguishable from your average real-estate salesman except for his cowboy hat. The hair is cut regularly, the face is rounder and clean-shaven, and the middle is spreading a little. Success has been pretty good for Jerry Jeff.

But if his appearance has changed, his music is still pretty much what he's been doing all these years. It still has that earthy, drunken, rambunctious quality, that good-natured humor and fun-loving exuberance and that same rough, sunburned voice. He may not hop freight trains anymore--maybe he never did--but he probably still gets an urge now and then to go runnin' naked through that hill country rain.

IF THERE IS anything different about Ridin' High from his previous efforts, it is that the hard edge of bitterness and scorn that sometimes sliced through the genial flamboyance is gone. Success has made Walker a little more easygoing, a little less mean. He no longer spits at the respectable people, as he did in the liner notes of his first major album, Jerry Jeff Walker. Describing two people who were the subject of one song, "Curly and Lil," he wrote, "Their warmth, independence, and self-respect prove to all those pussys who had to 'think of the kids and the old lady' that people can do what they want to decently."

He still admires people who sacrifice money and security for independence and freedom, but he takes a more charitable view of those who don't, as in one of the album's best cuts, a ballad called "Night Riders' Lament". One gets the impression that his friend Mike Burton wrote it as a sort of tribute to anyone who's ever done what he wanted instead of what he was expected to do. The narrator is a cowboy who fled the city for a simpler, older way of life, to the bafflement of his friends. One of them writes him a letter:

He tells me last night I run on to Jenny

She's married and has a good life

Ah, you sure missed the track

When you never came back

She's a perfect professional's wife.

She asked me

Why does he ride for his money

Why does he rope for short pay