The fearlessly eclectic conguero Ray Barretto was never much of a traditionalist. Though the Puerto Rican percussionist cut his teeth in some of the hottest Latin combos of the late ‘50s, he was a stylistic adventurer who was as comfortable improvising in the company of jazz greats like Cannonball Adderley and Lou Donaldson as he was laying down a rock steady salsa groove. Nowhere is Barretto’s genre-defying eclecticism better demonstrated than on his 1968 crossover smash Acid. This is salsa for the progressive set. Barretto was acutely aware that his audience was as likely to be grooving to Hendrix and Sly as to Tito Puente and Celia Cruz, and the frantic, soul inflected workouts of tracks like “A Deeper Shade of Soul” and “The Soul Drummers” are self-conscious but masterfully orchestrated invitations to this new audience. This is not to say that Barretto has abandoned his Latin Roots. Every track here is supported by a circular motuno piano riff and Barretto’s unstoppable Latin rhythms, but these traditional elements are augmented by the exploratory spirit that would eventually make him one of the most successful Latin bandleader’s of his generation.