The theme of this year's Southwest Chamber Music season is “Musical Color and Imagination” — and it certainly does take imagination to seat J.S. Bach and John Cage next to each other at the musical dinner table. This week's concert is a study in contrasts: two Brandenburg Concerti and Cage's other-weirdly Atlas Eclipticalis. The former, of course, are the apex of classical ear candy — anybody who doesn't love the Brandenburgs is probably either deaf or dead. On the other hand, those who love Atlas Eclipticalis are probably so open-minded their brains are in danger of falling out. Cage used the Atlas Eclipticalis 1950.0, an atlas of the stars published in 1958 by Czech astronomer Antonin Becvar, superimposing musical staves over the star charts and correlating the size of the notes with the size of the stars. The piece can be performed by any entity, from a single soloist to a small chamber ensemble to a full orchestra. What does it sound like? A New York Times critic bluntly termed it “utterly, inconsequentially boring.” There are, after all, long periods of silence, which the listener can fill in however he/she likes. I, however, find it eerie, gorgeous, outrageous — Cage daring us to take the music and run with it ourselves. But then, I liked Andy Warhol's film homage to the Empire State Building, so don't go by me. Norton Simon Museum, 411 W. Colorado Blvd., Pasadena; Sat., Feb. 23, 8 p.m. Also at the Colburn School of Performing Arts, 200 S. Grand Ave., dwtwn.; Mon., Feb. 25, 8 p.m.; preconcert talks, 7:30 p.m.; $38, $28 seniors, $10 students. (800) 726-7147 or www.swmusic.org.