Hamburg-based trumpeter Birgit Ulher never misses an opportunity to challenge herself with new improvisational partners – even if she has to leave the country to do so. Take these memorable CDs. Although both are nine-track discs showcasing the trumpet’s reductionist style in a trio setting, the similarities end there.

Recorded in Oakland, Calif. in October 2004, Sperrgut finds Ulher in the company of local bassist Damon Smith and percussionist Martin Blume from Bochum, Germany. The drummer of course, is an old hand at kind of stop-and-go improvisation, with partners like British violinist Philipp Wachmann, while Smith has extended his interactions past the Bay area to play with Europeans such as German reedist Frank Gratkowski and Wolfgang Fuchs.

Five months later, Nordzucker Ulher is in Berlin with two countrymen. There’s cellist Michael Maierhof, another Hamburg resident, who usually composes spatial music, and Berlin-based alto saxophonist Lars Scherzberg, who not only plays with Europeans like Italian pianist Alberto Braida and Fuchs, but has a long-time affiliation with Brooklyn-based drummer Jeff Arnal.

With both CDs slotted firmly in a minimalist grove, it’s hard to choose one over the other. Nordzucker may have a slight edge however, since as a semi-working group, the players are much more familiar with one another. During the course of the related tracks they’re able to expose this-side-of-inaudible timbres as well as sudden voluble trills.

Nowhere on either of the discs is there an attempt to set up a soloist-rhythm section hierarchy, with Maierhof and Smith contributing as many percussive impulses as Blume’s drum kit. While Blume’s polyrhythmic showing includes motifs that directly relate to Kenny Clarke’s Bop cymbal pulses, he’d much rather draw a drum stick across his ride cymbal or detach it to let it vibrate in the air. Concurrently he ranges all over his kit, highlighting flams and ruffs from his snares and toms, leaning into dark pounding from his bass drum, scattering bounces and rebounds, and ringing small bells.

For his part Smith’s output includes blunt string pummeling and slapped staccato lines, as well as wooden thumps and bumps. There are extended shuffle bowing passages in the bull fiddle’s lowest register and sul tasto squeaks that replicate Ulher’s valve straining.

Never brassy, her collection of tubes, bell and valve maneuvering is less than understated, consisting in the main of spittle-engorged bubbling, chromatic tongue- stopping, rubato spetrofluctuation, throat growls and shakes. Midway through the CD, it sounds as if she’s whispering crabby nonsense syllables straight through her bell. Infrequently underemphasized wah wahs and tongue pops arise, making it seem as if she’s creating like an uneasy alliance between the style of Don Cherry and a military bugler’s mess call – although the bulk of her output is linear.

This horizontal improvising carries on to the other disc, with Scherzberg’s saxophone using body tube resonation and tongue slaps to meet Ulher’s contrapuntal twitters part way. When sul ponticello sweeps from Maierhof’s cello joins, it’s almost as if the timbres from all three are arising from one organism.

Role transference is rife here as well. Commonly the cellist’s spiccato pops and grainy percussive slaps serve as the pedal-point fulcrum on which the horns’ improvisations balance. Yet one variation finds the trumpeter expelling a pitch that resembles and almost replicates percussion. Glottal punctuation from the saxophonist sporadically performs the same function.

Nestled among the prolonged silences is an acknowledgement that polyphonic flanges created by the horns come from metallic instruments. This cumulative friction binds the rubato slaps, pops and spits into heavy pressured reverberations. This sibilant power is one of the few aural entities that sets Sperrgut apart from Nordzucker. As examples of exploratory modern improvisation, however, both deserve attention.

— Ken Waxman

Track Listing: Sperrgut 1. 6.30x1.60x3.25m 2. 0.05x0.15x2.40mm 3. 0.02x0.90x1.20m 4. 2.10x0.95x4.05m 5. 1.85x3.30x5.20m 6. 0.50x0.20x6.30m 7. 3.00x5.10x7.00m 8. 5.05x4.50x3.20m 9. 0.10x1.20x1.80m

Personnel: Sperrgut: Birgit Ulher (trumpet); Damon Smith (bass); Martin Blume (percussion)

Track Listing: Nordzucker: 1. 88gr 2. 65gr 3.49gr 4. 43gr 5. 46gr 6.34gr 7. 61gr 8. 50gr 9. 63gr

Personnel: Nordzucker: Birgit Ulher (trumpet); Lars Scherzberg (alto saxophone); Michael Maierhof (cello)