At first, it was a hoot because of all of the bands you could see for a dirt-cheap flat fee. After several years, it has become a better-be-there confab whose Catholic programming impressively unites an audience that sometimes doesn’t recognize itself in the mirror. Meaning, the Winter JazzFest is a rather crucial gathering these days. The math speaks for itself: two nights, five venues, 60 groups. The music is constant. But the ’tween-show conversations are key as well. Appraising, positioning—the performance parade (with artists easily accessible) makes the event a forum of ideas. If you want to know what’s happening in New York jazz right now, you’d be a cluck to stay home. This year’s must-sees? Nels Cline Singers, Michael Blake’s Hellbent, SIFTER, Burnt Sugar, and Mostly Other People Do the Killing. And prepare yourself for a goosepimple or two when Joel Harrison offers his Paul Motian salute.

Fri., Jan. 6, 8 p.m.; Sat., Jan. 7, 8 p.m., 2012