What is "free" in freely improvised music? For many improvisers, "free" means loosing the shackles of notated music, eschewing tonal composition, shunning traditional concepts of melody, and best of all, dissolving the boundary between practice (especially rote drills) and performance. The results often bristle with points and spikes—intuitive, instantaneous manifestations of the jarring contrasts, tectonic shifts in volume level, and perpetually flowering dissonance that took serial composers like Anton Webern and Milton Babbitt years, months, and weeks to make.

Yet some improvisers find freedom on a bigger scale. The Amsterdam-based ICP Orchestra takes a catholic approach, pilfering music from multiple eras and stitching the results into a shambling sonic tatterdemalion. Under the direction of pianist Misha Mengelberg, an integral part of the 1960s Dutch free-jazz scene, the ICP Orchestra makes freely improvised music fun, ranging and rampaging from those aforementioned lyrical points and spikes to Dixieland jazz to waltzes and tangos.

Featuring 10 of the top improvisers from Amsterdam's celebrated jazz scene, including reedmen Ab Baars and Tobias Delius, Tristan Honsinger on cello, and violinist/violist Mary Oliver, the ICP Orchestra brings drama, wit, and virtuosity into freely improvised music. Lesser musicians might buckle under such willful eclecticism and devolve into puerile pastiche, but the ICP juxtaposes diverse and diverging musics with respect and love. The ICP's members are composers too—ICP stands for Instant Composer's Pool—creating pieces for the group to improvise in, through, and around. The visual highlight of the group is master percussionist Han Bennink, whose playful willingness to apply his drumsticks to any surface adds to the ICP's infectious, rambunctious fun. CHRISTOPHER DeLAURENTI

ICP Orchestra performs Sat Mar 25, Seattle Asian Art Museum, Volunteer Park, 1400 E Prospect St, 547-6763, 8 pm, $14/$16.