Cambridge, Mass. — As a musical cause celebre, it is safe to assume that Robert Hunter will never be as popular or as ''thrilling'' as Michael Jackson. But then, Michael Jackson will probably never write a song titled ''Mississippi Halfstep Uptown Toodleloo,'' either.
Hunter, who plays rhythm guitar and sings, is one of a number of now not young and not struggling artists who came out of the 1960s popular music scene. But Hunter would not want to be thought of as popular. Serious, maybe. Uncommercial, definitely.
For those who have followed the '60s music, Hunter is the legendary lyricist for the group that's been called ''the band beyond description'' - the Grateful Dead. But Hunter never plays with Jerry Garcia and the Dead.
Instead, Hunter helps to keep alive a musical tradition that goes back who knows how far - that of the solo performer, the troubadour who tours the countryside playing small houses and night spots, taking seriously the idea of musical art as a simple but powerful ''human scale'' experience between audience and performer. It is the folk tradition of standing alone under the grease lights and singing away for hours. In its own way, it is a heroic tradition, and Hunter plays it well - blending a freight-train strum with Leo Kottke-like vocals and earthy ballads, as he did for an appreciative audience in Cambridge, Mass., recently.
Backstage between sets, I asked Hunter if he had grown tired of touring alone. ''Not really,'' he said, ''one of the pleasures of soloing is that I can do whatever I want, come to the song and the evening with whatever is in me; I can test new songs, new ideas. If I want to play 'Truckin' (a spirited Hunter/Garcia tune) as a slow ballad, I can do it.''
''I still love playing music, even if I don't consider myself primarily a musician - I'm a lyricist.''
Hunter's lyric roots are in the ''San Francisco renaissance'' - that surge of creative artistic ferment in the Bay Area during the late 1950s that brought the beat writers and poets to national attention. For a time, Hunter hung around Neal Cassidy (the model for Jack Keroac's protagonist Dean Moriaty in ''On the Road'').
In 1961 in Palo Alto he met Jerry Garcia. The two lived out of their junk-heap cars, ate crushed pineapple from huge Army surplus tins, and plotted musical strategy. Soon they started a band called the Thunder Mountain Tub Thumpers and began experimenting with different forms of acoustic music. And though it wouldn't be long before Garcia (whom some consider the most accomplished lead guitar player in the world) moved into the circle of friends that eventually became the Grateful Dead, and Hunter moved away to write - the two got together again during the sunset of the '60s. By that time Hunter had sorted out his literary act, and his imaginative verse added depth and dimension to a band known primarily for its ability to jam indefinitely.
Music critic Les Kippel, who has followed Hunter for years, says that even during the '60s when everyone was letting it all hang out, ''Robert was very serious about his writing, very sensitive - and very good.''
Not to overstate Hunter's ability, since Shakespeare he isn't. But in relation to the sometimes trite love songs found on many radio stations, Hunter does sophisticated work. His folk songs are influenced by both a hip and a hobo sensibility, written for the old-time wilderness adventurer who today, perhaps, is a computer programmer and member of the Sierra Club. It is no-frills music incorporating street wisdom, nostalgia, and love stories (understated). As he says, ''I work hard to make each song different.''
If early on Hunter was true to the 20th-century American artistic tradition of spurning the old in search of the new, it sounds as if today Hunter is starting to go back over the tradition. ''I'm reading Wallace Stevens again,'' he says. ''He is a master with words.''
Hunter is also sounding more traditional and is making statements about the health of the country: ''If we are going to have a strong nation we are going to need strong individuals - and that means a strong ethical sense.''
Do such statements mean he is getting more conservative?
''Well for one thing, I don't shoot off my mouth so much about things I know nothing about.''
What else has changed his viewpoint?
''I'm raising kids now. They don't care about the Grateful Dead or our reputation - don't care about the music. This used to aggravate me, but now I'm trying to see it as a learning experience!''