Among the wind instruments typically used in jazz, the trombone–essentially a giant slide whistle–might be the most challenging when it comes to intonation. Luckily for trombonists, jazz listeners have learned to accept a degree of imprecision from the instrument–which makes the pinpoint virtuosity of Conrad Herwig stand out all the more. In every generation there’s been a handful of trombonists capable of nailing every note at tempos that would make a saxophonist blanch, but unlike some of his predecessors, Herwig has always placed communication above sheer technique. In recent years he’s been absorbed in Latino music and culture, working in bands led by pioneers Mario Bauza and Eddie Palmieri and, as a leader, applying Latin rhythms to the repertoires of John Coltrane and Miles Davis. His latest, Sketches of Spain y Mas (Half Note), was recorded with a nonet, but tonight’s audience will have the rare chance to hear him in the less intense and more exposed setting of an acoustic quartet. a 9 PM, Pete Miller’s Seafood & Prime Steak, 1557 Sherman, Evanston, 847-328-0399. F A