For those who think, based on recent recordings, that guitarist Bill Frisell has lost his edge, two new recordings should go a long way to restoring faith in Frisell's inestimable abilities as a composer and performer. They also assert that, like them or not, the Americana, world music, and groove-centric concerns of his most recent Nonesuch releases are by no means the work of a man resting on his laurels. Frisell has always had a voracious musical appetite, as content to strum a simple chord as he is to explore the inner workings of writers including Charles Ives and Aaron Copland.

A forthcoming new recording of his longstanding trio collaboration with drummer Paul Motian and saxophonist Joe Lovano ( I Have the Room Above Her , out February 8 on ECM) shows his ability to improvise freely in a more abstract and ethereal fashion is completely intact. And, as Richter 858 proves, not only is Frisell still capable of challenging composition that bridges the gap between form and freedom, he is a constantly evolving artist who continues to incorporate his own growing interests in new and intriguing ways.

Originally composed for inclusion with a book celebrating the work of German painter Gerhard Richter and now finally seeing the light of day as a standalone work, Richter 858 places Frisell, his guitar, and arsenal of electronics in the context of a contemporary string group with cellist Hank Roberts, violinist Jenny Scheinman, and violist Eyvind Kang, all past and recent collaborators. The opening minutes of "858-1" are as aggressive, angular, and abstruse as recent efforts including Blues Dream and Unspeakable have been easy on the ears. If, indeed, there's any precedence in Frisell's compositions here, it's with the more adventurous music of This Land and Before We Were Born —inescapably daring, yet with an indefinable American, if not Americana, complexion.

One element that is a continuation of Frisell's more recent work is his approach to improvisation, which leans more to the collective and less on the individual. And the lines between structure and soloing are inevitably blurred. "858-5" may revolve around a repeated rhythmic motif from all players, but everyone seems to have their moment(s) of extemporization, although it is often difficult to figure out how they determine who will carry the form and who will become more exploratory. "858-6" bears the ethereal microtonal ambience of Gyorgy Ligeti's work, while "858-4," the longest of the eight pieces, begins as an atmospheric tone poem, ultimately evolving into a cello ostinato that allows Kang and Scheinman more breathing space while Frisell applies colours with his sundry electronic devices.

Richter 858 may scare aware recent converts who enjoy Frisell's more folksy nature. But for long-time fans, it's a reassurance that Frisell hasn't gone soft, rather that he simply chooses to explore the broader concerns that his insatiable musical interests demand.

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