The sign of a true musician is one who assimilates a broad diversity of influences, and creates a distinctive voice and personal musical language. Guitarist Kurt Rosenwinkel has been moving in that direction for a number of years; following his angular post-bop album, The Next Step, he has finally arrived with an album that is as much Radiohead as it is Zawinul, as much trip hop as it is bebop. Heartcore creates a new sonic space for improvisation; challenging while, at the same time, completely accessible.

When Rosenwinkel was advanced the money for this recording in 2001, he spent the lion’s share of it to acquire an advanced home studio for himself. This allowed him the latitude to work on the recording whenever he pleased, without the restrictions and costs of having to worry about booking time in a recording studio. A great deal of time was spent just learning how to make all the equipment work together, and there were a lot of snags. But, in the end, the result is a recording that pushes the boundaries of contemporary music, and operates in its own harmonic and rhythmic universe.

Rosenwinkel was able to spend hour upon hour recording various tracks on his own, including guitar, keyboards, drums and programming, then calling in band mates, reedman Mark Turner, bassist Ben Street and drummer Jeff Ballard, to contribute additional tracks to the blend. Working in such an isolated environment is a double-edged sword: there is as much time as one wants to experiment with parts and sounds; but there is the danger of becoming too close to the work, losing sight of the bigger picture. Fortunately, Rosenwinkel had the good sense to bring in hip hop producer Q-Tip, of A Tribe Called Quest, for additional ideas and an overall perspective on the work. Working together they have created an album with a distinct arc; a conceptual whole that defines a new way to compose as a basis for improvisation. Rosenwinkel has said that he sees a correlation between the works of 20th Century composers like Schoenberg, and hip hop; how disparate sounds and phrases in theory should not work, but somehow manage to. Heartcore is filled with such conundrums, but that is only a part of what makes it so intriguing.

Heartcore is a genre-bending recording that owes to many different sources. Rosenwinkel continues to develop his own language as a guitarist; his sound is thick and slightly grungy, owing as much to John Scofield as it does to Pat Metheny. The rhythms vary widely, from the post-bop "Blue Line" to the more trip hop groove of the title track. World music influences, as in "Thought About You", are completely assimilated into the new language. Washes of sound ebb and flow; some of the synth sounds are reminiscent of Zawinul, but feel more organic. Mark Turner, when given reign to improvise, shows why he is unquestionably one of the most under-rated saxophonists in the US today.

While the textures and playing make Heartcore worth listening to, what is also clear is that Rosenwinkel is continuing to develop as a composer. Melodic lines which are odd, yet strangely lyrical and compelling, drive the majority of the pieces. Guest Mariano Gil’s flute on "Love in the Modern World" at first makes it sound like the soundtrack to a Spike Lee film; but the electronic washes and injections are never far away, making this sound more like a soundtrack to an alien landscape.

Rosenwinkel’s first two records for Verve, 1997’s The Enemies of Energy and 2000’sThe Next Step, were ideal for playing in small clubs, like the now-defunct Small’s in New York City, where Rosenwinkel and his quartet held regular residence. With Heartcore, however, Rosenwinkel and Q-Tip have upped the ante, creating a record that is more suited to the larger venues that Rosenwinkel now finds himself in. Other-worldly, yet completely compelling, Heartcore signals a shift in direction from an artist who has gone from being one to watch out for to one who has arrived.