Familiarity and novelty are the two strategies that can work equally well in improvised music. That’s why CDs with almost the same personnel can sound so different.

Consider the depth of penetrating understanding that goes into the duo session by two Englishmen, multi-reedman Paul Dunmall and bassist Paul Rogers, and contrast it with the interactive first-time meeting between American bassist William Parker and Dutch reedist Ad Peijnenburg. Similar on the surface, both discs define cooperative duo playing. But both arrive at that concordance differently.

Longtime members of Mujician with pianist Keith Tippett and drummer Tony Levin, as well as mates in larger bands led by Dunmall and Tippett, the reedist and bassist first recorded as a duo in 1988. Giving Rogers an opportunity to show off his A.L.L. 6-string bass, each track on AWARENESS RESPONSE features Dunmall on a different horn: border bagpipes, tenor or soprano saxophone.

In contrast, except for one track playing sopranino, Eindhoven, Holland-based Peijnenburg sticks to his main horn, the baritone on the other five tracks. Founder of the international saxophone sextet The Six Winds, which has included Danish altoist John Tchicai and Washington, D.C. tenor man Andrew White among others, Peijnenburg’s other main band features South African percussionists Thebe Lipere and Louis Moholo.

With no strings attached to his improv conception since the mid-1970s, the Dutchman altered his game plan and toured and recorded with Parker for the first time late last year. Someone whose range of activities have included partnerships with nearly every major contemporary saxman from New York’s Charles Gayle to Chicago’s Fred Anderson, Parker was an easy fit. As a first-time duo session, though, his and Peijnenburg’s playing is a lot more cheerily anarchistic than Dunmall and Rogers’ methodical sound triptych,

Featuring his main axe — the tenor — on the second track, Dunmall honks out scattered tone patterns as Rogers responds with guitar-like flat picking that glides from the centre up to the tuning pegs. When the saxman moves into reed-biting, squealing and squeaking with an intensity vibrato, Rogers follows suit, producing banjo-like flailing, rapid runs and careful finger picks. As the tenorist rasps out irregular pulses, circular trills and obbligatos, the bassist creates an accompanying pattern filled with double and triple stopping and circular strums. Using string snaps, slurred fingering and staccato stops, Rogers ends with a crescendo of rotating thumb picking that could have fit in with such British folk-rock bands of the 1970s as Pentangle — if it played free improv.

Throughout both men seem to be playing all the time, and this carries onto “Pressure Response”, Dunmall’s bagpipe feature and “Precious Response” for soprano saxophone. On the later, under-the-breath trills and fibrous obbligatos soon lighten as Rogers creates voluminous, abrasive spiccato tones. Once the arco bowing take on locomotive power with ponticello accents, the saxist exposes trilling ghost notes that soon meld with Rogers’ output. When Dunmall’s swelling smears and twitters get louder and faster, they’re pushed aside by triple stopped basso and forced intermittent timbres from Rogers that are as diffuse as they are continuous.

Arm-operated bellows for his south Scotland bagpipes give Dunmall viscous waves of sound on “Pressure Response”, to which Rogers responds col legno and sul ponticello. With one set of responses woody and the retorts booming as well, the textures become almost too thick here. Finally the bassist surmounts the vibrating, buzzing tones with an impressionistically tinged legato line that soars above the pipes’ pressure.

Reed-biting and kazoo-like timbres make Peijnenburg’s sopranino saxophone playing stand out on “Streetwise”, even on the freewheeling improvisations that make up BROOKLYN CALLING. As a matter of fact, quick chirping twists and vibrated flutter-tongued turns so take up the circus music reminiscent melody, that Parker’s strumming almost fades into the background.

This isn’t the case on other tracks such as “Many Things”, where by the last third the bassman’s ponticello tones and vocalized shouts of “where’d he go” presage harsher, sharper and spikier bent notes from the bull fiddle and some tandem string stretching and syllable scatting. The piece begins with tough, repeating Aylerian glossolalia from the baritone as Parker constructs a bouncing pulsation beneath it. When Peijnenburg introduces irregular pitches and flutter tonguing, the bassist, pizzicato, begins accelerating the tempo in miniature motions so that it’s soon moving one-and-one-half speed quicker than before. Martial reveille, doits and growls enter the air from the sax, which leads to Parker’s spiky scatting.

“Clear Stray” is almost 15 minutes of elongated wind tunnel exhortations from baritone sax, while “Notes from Heaven” offers nearly 20 minutes of mellow, subterranean baritone lines. On the first the saxman uses the trick of creating a bugle-like martial anthem and wriggles the notes every which way as he plays mid-range variations on the theme. His snarling repeated note pattern start to sound like “Mad Lad” saxophonist Leo Parker’s seminal blues-bop from the 1940s as bassist Parker — no relation — responds with bouncing, staccato arco lines. On the second piece, the bassist moves from sul tasto to widely-spaced plunks to constrained walking bass, the better to deal with the baritonist’s output, which interspaces snorts, deep, metallic resonating body tube vibrations and renal constraint.

“Pretty Easy”, the concluding track, even shows the two operating in an avant-garde balladic mode — sort of an updated Harry-Carney-meets-Milt-Hinton fashion.

When Peijnenburg’s subterranean tones dissolve into pure breaths at the end, the newly minted duo have proven they can handle any time and tempo and make it interesting — as do the two Pauls on the other CD.

— Ken Waxman

Track Listing: Awareness: 1. Pressure Response* 2. Priceless Response+ 3. Precious Response#

Personnel: Awareness: Paul Dunmall (border bagpipes*, tenor+ and soprano# saxophones); Paul Rogers (A.L.L. 6-string bass)

Track Listing: Brooklyn: 1. Notes from Heaven 2. Many Things 3. Streetwise* 4. Clear Stray 5. Pretty Easy

Personnel: Brooklyn: Ad Peijnenburg (sopranino* and baritone saxophone); William Parker (bass)