Reprinted from yesterday's late editions.

In these days of sonic overkill, it's hard to imagine one man with just an acoustic guitar keeping the attention of a crowd for very long. But because John Martyn, who appeared at The Cellar Door Wednesday night, is one of the most unusual instrumentalists - and singers - ever to come out of Great Britain, it is a problem to which he is immune.

Like most players who make their living from an acoustic guitar, Martyn comes out of a folk music background. He played around his native Scotland and England for years, soaking up traditional songs like "Spencer the Rover," still part of his standard set, before developing unique personal style that owes as much to jazz and the blues as anything else.

It's for that reason that the warning preceding Martyn's rendition of Skip James' "I'd Rather Be the Devil" - "purists, eat your hearts out" - was quite appropriate. The way Martyn caressed the word "anywhere" on "Solid Air," giving it a different pronunciation and intonation each of the half dozen times he said it, seemed to make him a particularly precocious pupil of Billie Holiday, just as his experimentation with various electronic devices makes him the Jimi Hendrix of the acoustic guitar.

Martyn's use of fuzz, feedback, wah-wah and echoplex is unprecedented for an acoustic guitarist, and the galaxy of effects he gets from his little boxes gives a whole new dimension to this art.