Results of a 30 year Manhattan friendship, Japanese-born pianist Eri Yamamoto and local pianist Matthew Shipp first met when she had a solo gig in an East Village club. Moving in the same advanced music circles and working with the likes of William Parker, Daniel Carter and Hamid Drake, both have recorded solo and in many groups, but never as a duo.

The horizon that's stretched here is the adaptation of two keyboard interpretations into a comprehensive whole. The five tracks move and are carefully balance among relaxed and nearly romantic ballads, tough galloping cadences and serpentine reflections. As the pianists intersect textures from the 176 piano keys, one frequently digs into pedal patterns while the other tinkles celestially high keys. Hints of blues progression and criss-crossing flexible pattens even are heard on "New York Piano Forte" that move to languid reflections and then return to bluesy cadences before concluding the session with a processional interlude.

Although situated on the left and right channels in the mix it's often difficult to identify exactly who plays what. But that's part of Horizon's achievement. Pointed rebounds and rooted quivers are jointly projected on "Avenue B Social Club" — composed by Yamamoto to recall her initial East Village gig — and illuminated by pressurized swing. During the min-concerto which is the nearly 10 minute title track, the blended sequences move from relaxed story telling that shifts from one to the other, slinky distinct note emphasis and a final section in which both lay on the pressure to create tensile rumbles which clang then slither away.

Sympatico as well a sophisticated, Yamamoto and Shipp prove that good friends can create memorable music probing all the timbres from the dual mini-orchestras which the pianos represent.