With ¡Bien Bien!, as with previous releases, trombonist Wayne Wallace and his group display a very subtle kind of mastery. The elements of the combo's excellence are impressive enough. First, Wallace plays his instrument as beautifully as the trombone all-stars in Manny Oquendo's classic Conjunto Libre—or indeed the great Julian Priester, who sits in on a couple of numbers on ¡Bien Bien!. Second, the group deploys an irresistible laid-back groove, befitting their Bay Area roots; there is room to breathe here, in contrast to some Latin jazz derived from the breakneck New York salsa scene. (San Francisco's North Beach jazz scene is memorialized here on "Mojito Café.")

That combination of factors coalesced into something truly great on their The Nature of the Beat (Patois, 2008), which covered Ray Charles, the Miles Davis Nonet, "Bésame Mucho," and Earth, Wind & Fire, in a most appealing way. But the instrumental prowess and good-time groove only explain so much; there's something else present on a track like Nature's "That Walk," which starts off sounding merely like exceptionally competent genre jazz, but winds up transporting the listener. Wallace would surely call that secret ingredient a duende, a Spanish word denoting a spirit: in this case, something ancient encoded in the musical forms that's released by the musicians.

If that duende is present on ¡Bien Bien!, it's most likely lurking in "Africa"; uneven, but with sufficiently many high points to rank right up there with Tito Puente's "Equinox," from his live El Rey (Concord Picante, 1984) with the fantastic Jorge Dalto on piano sounding like a young Herbie Hancock), among the finest Latin jazz versions of John Coltrane numbers. The piece begins with very Love Supreme-era Coltrane-like incantatory statements by Wallace and pianist Murray Low and proceeds to a statement of the familiar theme that stupendously uncovers previously unsuspected Latin profundity in the song. Low later delivers a marvelous solo that effortlessly weaves massively lyrical, McCoy Tyner-like phrases (Tyner being the pianist on the Coltrane original), together with elegant Cuban-style figures.

If the mysterious duende were scrutinized under the microscope, part of its secret would surely lie in the mastery of both jazz and Latin elements. Wallace and company draw deeply on both sides of the Latin jazz equation, a balance that is rarer than it first appears: most practitioners are substantially stronger in one or the other elements.

Another, more prosaic, hypothesis about the duende: it has a lot to do with singing. ¡Bien Bien! features singers Orlando Torriente and Kenny Washington trading verses in Spanish and English, backed by a spirited coro, on a fine rendition of Eddie Harris's "Freedom Jazz Dance," but no other vocal tracks. Nature of the Beat, simply put, had more numbers with this vocal configuration, and the earlier record accordingly soared more frequently. This is a quibble momentarily forgotten, however, as the quintet cruises through most of the singer-less material on the more recent disc.