The mission of Preservation Hall is right there in its name — preserving the traditions of jazz, arguably America’s greatest cultural innovation, in its acknowledged birthplace of New Orleans. If that mission sounds academic on paper, it’s a blast in practice, as the legendary Preservation Hall Jazz Band proves on Preservation, a benefit album for the hall itself as well as its youth-oriented Outreach Program. Each song pairs the PHJB with a guest vocalist, and there are some serious heavy hitters here (Tom Waits, Ritchie Havens and Merle Haggard, to name a few), all of whom blend humbly and seamlessly with the band, never losing sight of the album’s objective. PHJB’s timeless hot jazz is as vibrant and essential as ever, and hearing so many artists step outside their wheelhouse to perform this music is fascinating. Highly recommended.