Judy Collins and Jack Elliott rate every accolade for making Summer Folk Concerts' first presentation the finest folk presentation in Cambridge in many months.

Miss Collins, in white, appeared first, petite and stern, laughing yet intense. Aided by her guitar's subtle nuances, driving rhythms and vibrant lilt, she toyed with her audience for nearly an hour. She sang with them until they caught her playful spirit, then to them, then about them. She laughed with them at the cleverness of an Illinois coffeehouse, called Know Where, cried with them at the tragic death of Medgar Evers, cajoled them with a traditional devil song, caught them with a hammering message of the modern devil. "Masters of War."

Throughout, her voice enveloped the hall: awe-inspired, wild applause followed every song. "Why does she have to quit?" a disappointed summer school girl moaned after Judy's second encore. "She could sing like that for hours," said another.

Judy Collins is a "folk singer" par excellence, but Jack Elliott is "real folk," and the contrast provided as exciting a concert as as folk music fan could hope for.

Doffing his cowboy hat to the initial applause he proceeded to sing the best from every major songbag of rural America--he sang Leadbelly in his dialect, Blind Lemon Jefferson's Black Snake Moan (as dirty a blues as could be if one listens twice, but which Jack pretends is as clean as an Ivory-washed babe), Cisco Houston, Woody Guthrie, Eric von Schmidt and a dozen other folk classics.

But the magic emanates not from the song alone, but the man, whose every movement is classic, whose Western drawl is definitive, who can mug and joke, yodel and moan, tell a tall tale ("I don't believe in rebearsin' for recordings: and I never listened to them afterwards") so well that he has to explain that it was a slight fib after all.

In this "hootenanny" world it is a blessing to discover that folk music can still be tasteful and exciting. On the basis of this first offering, one should not miss the second Summer Folk Concert July 21.