The avant-garde composer and multireedist Anthony Braxton had plenty of words for his admirers at Le Poisson Rouge on Friday night, when it was officially his turn to take the stage.
He talked about the striving of noncommercial artists. He referred to geopolitical dynamics," adding that the world was still full of men and women of goodwill." He expressed appreciation for the costume splendor of Lady Gaga. And finally he struck a note of retirement-party humor: If you have to be 65, this is the best way to do it."
Mr. Braxton, bespectacled and cardiganed as usual, was a hands-on honoree during Tri-Centric Modeling: Past, Present and Future, a two-day festival commemorating his legacy as well as his age. With proceeds going to the nonprofit Tri-Centric Foundation, which supports performances and archival preservation of his music, the festival gathered a marvelous cohort of his proteges and peers, outlining something like a living index of contemporary improvised music.
The terms of genre have always been problematic for Mr. Braxton. The music that he presented on both nights, however infused with spontaneous actions, was the furthest thing from improvised. On Saturday, at the Issue Project Room in Brooklyn, there were excerpts from Trillium E," an opera he recorded this spring. Fridays concert culminated in Composition 361," a 20-minute work for Mr. Braxtons 12+2tet: his primary public outlet of late, stocked with woodwinds, horns and strings.
Among other things, Composition 361" conveyed the impression of a great beast given to disarmingly graceful movements, like a hippopotamus in water. A general rumble at the outset gave way to a succession of internal alliances: between, for instance, Sara Schoenbeck on bassoon and James Fei on alto saxophone, sketching interlocking motifs; or between the guitarist Mary Halvorson and the flutist Nicole Mitchell, with a zipperlike ascending run. On the whole, the piece was wily and ungraspable.
That sense of the enigmatic was a common thread among the artists who had earlier appeared. Ms. Mitchell, representing Chicago's Association for the Advancement of Creative Musicians, led a version of her Black Earth Strings, with the violinist Rene Baker and the cellist Tomeka Reid. Their music was terse but buoyant, enlivened by tonal frictions.
The evening began with a droning bagpipe processional, played in the dark by Matthew Welch as he circled the room. The alto saxophonist Steve Coleman and the trumpeter Jonathan Finlayson followed with a circuitous duet, variously pointillist or boppish. Mr. Coleman hailed Mr. Braxton afterward: If it wasn't for you, we wouldn't be here.
Another alto saxophonist and composer, John Zorn, restated that sentiment after his riveting stand with the trumpeter Dave Douglas, the bassist Brad Jones and the drummer Gerry Hemingway. They played a tune apiece by Mr. Zorn and Mr. Douglas, snapping between airtight melodic forms and a fierce, expressive scrawl. A similar duality cropped up in Opus 23D," an old theme of Mr. Braxton's that they tackled with hard-nosed respect.