Mark O'Connor may not be exactly a household word in most households, but anyone who has ever dabbled in fiddling (or related types of music such as bluegrass) knows him as the unchallenged champion of contest fiddling.

The Seattle prodigy first entered the National Old Time Fiddlers Contest in Weiser, Idaho, in 1973, in the 12-and-under age category - only seven months after he started playing the instrument. He won second place.By the time he retired from contest fiddling in 1984 (to move to Nashville for a career as a session musician and solo artist) he had accumulated nine first-place and three second-place finishes at Weiser. He was the first contestant ever to have a run of four victories in the championship, or open, division.

He also changed contest fiddling forever. His "progressive" fiddling style, jazz-influenced and improvisational, turned a whole generation of young fiddlers into Mark O'Connor wannabees - to the chagrin of some old-timey players unhappy that more traditional styles had fallen out of favor.

The Country Music Foundation has now released "Mark O'Connor: The Championship Years," a collection of 40 previously unreleased, live recordings made during the Weiser contests of 1975 through 1984. O'Connor himself suggested the project and selected the tunes and performances that he feels best represent his contest playing and his growth and development as a player, according to press materials.

The album certainly accomplishes that. This is obviously an album targeted mainly to fiddlers and hardcore fiddle fans ("Grey Eagle," "Clarinet Polka" and "Herman's Rag" may be great tunes, but how many casual listeners really want to hear three different versions of each on the same album?) In fact, in an attempt to document changes in O'Connor's personal style over the years the album sounds a little like some fiddle contests - the same standard tunes repeated over . . . and over . . . and over.

However, "The Championship Years" offers enjoyable listening even for those who might ask "Mark who?" O'Connor is an incredibly talented musician by any standard, and this album offers a sampling of contest fiddling at its best. The sound quality is very good despite the fact that it was compiled from live, on-stage recordings, no doubt thanks to Weiser's excellent sound system.

The album is available by mail order from Country Music Foundation Records, 4 Music Square East, Nashville, TN 37203. Price is $10.89 for cassette or $15.98 for compact disc, plus $2 for postage and handling. For credit-card orders, call 1-800-255-2357.