That old standby of rock and jazz, the guitar, has been having some hard times in recent years. Beset by iron-wristed hard rockers and scientifically precise fusion clinicians, the instrument has suffered from insensitive and overbearing abuse.

There are, however, a handful of musicians who are keeping the grand traditions of the guitar alive. Jazz, rock, you-name-it guitarist Larry Coryell is one of them.

His set last night (he will also apppear tonight) at the Cellar Door, was a dazlling display of musical and technical expertise. Playing acoustic 12- and six-string, and electric guitar, he cut across all the stylistic barriers, suggesting the intriguing sound possibilities of the guitar.

His soulful version of Horace Silver's "Song for My Father" was a rhythmic delight, with percussive strumming set against the distinctive themes. Throughout, Coryell avoided the temption to let his fast fingers and deft chord work get out of control. "My funny Valentine" (played on electric guitar) featured soft, melodic sections that were contrasted by lightning-like barrages of notes.

Larry Coryell has an agile and enthusiastic musical mind that gives his work a sense of character that is lacking with many of his musical counterparts. He is a guitarist's guitarist.