The recent On-U Sound reissue program through Japan's Beat Records has been a kind of heaven for longtime followers of the London dub/reggae label. For newcomers bewildered by the stream of titles, a new megamix "On-U Sound Crash," by the label's founder and producer, Adrian Sherwood, could be the perfect introduction: Snippets from over 30 tracks, by over a dozen of the label's core artists, are slashed, mashed and rudely dispatched here.

Dub has always been Sherwood's passport to a land of pure experimentation rather than an excuse for knocking out formulaic reggae. Hence roots-reggae classics from Creation Rebel and African Head Charge jostle up against the heavy electro/metal-funk onslaught of Tackhead and Mark Stewart's paranoid industrial noise, all treated to the filters, flangers and echo-box madness of Sherwood's mixing-desk.

His selection is dominated by selections from On-U's heyday, from the early 1980s up to the early '90s. Underground MC celebrity Gary Clail, who became a full-fledged pop star with the Top-10 success of his 1991 "Human Nature" single, is represented here by perhaps his best track, "Two Thieves and a Liar," a driving, bass-led groove over which he rants about the deceit perpetrated in London's financial district.

For the already initiated, there are no real surprises on "On-U Sound Crash," just plenty of pleasurable memories from the last two decades. But new arrivals should be taking notes. his sophisticated, but with NMS you get both musical maturity and a great time.