A lyricist for the Grateful Dead, Robert Hunter has freely associated images and aphorisms just as the band has freely associated notes and chords. Appearing as a solo folk singer at the Cellar Door last night, Hunter took free association one step further. He segued his way through at least 15 songs in a stimulating 40 minutes medley. The effect was cumulative as Hunter leaped from the Spanish motif of "Lucia" into the "Dead's Friend of the Devil," into the blues of "Alabama" and into the reverie of "St. Stephen."

Hunter sang Grateful Dead songs, tunes from his own two solo albums and unrecorded orginials. As a singer, he strayed in and out of key. His songs were often undisciplined in structure. But the hallucinatory quality of his images, combined with the streetwise sense of his aphorisms, overcame these obstacles.

The psychedelic music of the '60s may have been self-indulgent, but at least it expressed enthusiasm for experiences and ideas. Hunter's performance last night reflected both these strengths and weaknesses.

In the opening set, comedian Rich Shydner was right on target with his parodies of an arena rock group, a hillbilly stuntman, a stoned driver and a lawyer's TV commerical. Hunter and Shydner return to the Cellar Door tonight.