Rachael Yamagata knows that a sizable portion of her audience might never hear her new album the way she intended. Due this week via Warner Bros., "Elephants ... Teeth Sinking Into Heart" consists of 15 tracks spread over two CDs, one with ballads and one with rockers.

The idea, the New York-based singer/songwriter says, was to present "two different sound experiences" in a manner that preserves the emotional purity of each. "Of course, it's all going to end up on iPod Shuffle anyway," Yamagata says with a laugh. "I accept that that's how it goes these days. But I didn't want to help that process along."

As its atypical presentation suggests, "Elephants" reintroduces an artist who has undergone some changes since the release of her 2004 debut, "Happenstance," which has sold 156,000 copies in the United States, according to Nielsen SoundScan. That album slotted easily into the early-'00s girls-gone-mild craze that erupted in the wake of Norah Jones' success. But the new disc is an artier, more cerebral affair, with introspective arrangements full of chamber-goth piano and jagged-edged guitar.

The first disc's centerpiece, "Sunday Afternoon," stretches beyond the nine-minute mark. "This record isn't really going for mass appeal," Yamagata says. "Nothing on it strikes me as a traditional pop-radio hit. If anything breaks, it'll be because the audience was waiting for this kind of sound."