Drummer Tom Tilton and pianist Joe Bonner continue a 25-year relationship with Spring Impressions in Jazz, Friday, April 7, and Saturday, April 8, at Vartan's Jazz Club, a program that promises both creative arrangements and a fresh instrumental approach. Bonner, who has played with such giants as Pharoah Sanders and Freddie Hubbard, has a solo CD of Thelonious Monk compositions about to ship from Evergreen-based Capri Records (Bonner and Monk share more than skilled eccentricity: Both were born in Rocky Mount, North Carolina). As an acknowledgement, a healthy dose of Monk is on the Impressions menu. As one of Denver's more open-minded drummers, Tilton tends to organize concerts that push artistic boundaries by bringing together poets, painters, dancers and the like. Expect something of that invigorating spirit at this affair, which assembles a talented quintet featuring Krishna Madehalli on tabla (an Indian dual drum), Mark Simon on bass and Peter Sommer on tenor, soprano saxophones and bass clarinet.