All band members, at one point or another, played improvisations asserting their independence.

Lonberg-Holm is most identified with playing free improvisation and free jazz.

The viola (or violinha) plays mostly variations and improvisations on the main rhythm defined by the two others.

Paul Hanson plays jazz fusion bassoon-an improvisation in an electric setting...

The two, joined by the bassist Calvin Hill, were having fun, playing casual, conversational improvisation, the sort musicians engage in after hours or at home.

A smaller bocú, called a quinto or bocusito, plays complex off-beat figures and improvisations.

And here was where Mr. Brecker took off, playing challenging, open-ended, sometimes abrasive improvisations.

Quietly, they traded off playing bass lines and improvisations on the chords; it was rehearsed, relaxed and extremely musical.

Percussionist Jim Meneses is the only member reputed to be musically active, touring the world playing free improvisation.

At the Knitting Factory on Wednesday night, the group sat in a semicircle, and at first played structured free improvisation.