Like Boston’s Greg Kelley and Berlin’s Axel Dörner, Austria’s Franz Hautzinger is a trumpeter whose improvisations rarely, if ever, employ that instrument’s traditional tone. But with his formidable technique and close miking (placing the microphone in the bell of the trumpet to achieve distorted, supersaturated tone colors), Hautzinger might be the most extreme of the three, dismantling conventional musical notions with a zest and focus that would make John Cage grin. On 1998’s Euro-jazz-oriented Speakers Corner (Extraplatte) he remained true to traditional intonation, as well as melody and harmony–although his quest for greater control of the sound palette had already led him to design a quarter-tone trumpet to access microtones with greater precision and fluidity. On his more recent work, however, the 39-year-old Hautzinger has jumped headlong into full abstraction. So far his most profound statement is Gomberg (Grob, 2000), a fiercely original solo recording that organizes a broad array of colors and textures with careful compositional logic. “Concert for Christina,” for example, consists largely of Hautzinger exhaling and inhaling through his trumpet; close miking expands the breathy sounds, adding harmonic depth to these columns of air. Careful valve manipulation and meticulous mouthpiece control add exquisite pitch variation and create eerie harmonic shadows. Hautzinger also has a wide range of popping and whispering sounds at his disposal, as well as a gently percussive effect arrived at by miking his valve mechanisms. In a nod to Cage, Hautzinger’s recordings leave in ambient sounds–an ambulance siren, chirping crickets, children playing. His work on this year’s recording with free improv pioneer and guitarist Derek Bailey was described (positively) by one writer as sounding like an “airlock in a plumbing system.” In his first visit to Chicago he’ll play in several different contexts. With bass clarinetist Gene Coleman on Sunday, October 20, 3 PM, HotHouse, 31 E. Balbo; 312-362-9707. Solo on Tuesday, October 22, 8 PM, Renaissance Society, Cobb Hall, University of Chicago, 5811 S. Ellis; 773-702-8670. In concert with members of the Northwestern University New Music Ensemble on Wednesday, October 23, 7:30 PM, Lutkin Hall, Northwestern University, 700 University, Evanston; 312-297-4808. Debuting a new piece by Yoshihide Otomo as one of several guests of Ensemble Noamnesia next Saturday, October 26, 8 PM, Museum of Contemporary Art, 220 E. Chicago; 312-397-4010.