At a moment when musical streams are crossing with unprecedented frequency, it’s crucial to remember that throughout its history, New Orleans has been the point at which sounds and cultures from around the world converge, mingle and resurface, transformed by the Crescent City’s inimitable spirit and joie de vivre. Nowhere is that idea more vividly embodied than in the Preservation Hall Jazz Band, which has held the torch of New Orleans music aloft for more than 50 years, all the while carrying it enthusiastically forward as a reminder that the history they were founded to preserve is a vibrantly living history.