It’s hard to know exactly how to introduce Patricia Barber.

To some, she’s a composer, adding her impressive and important voice to the ever-changing musical source that we call the jazz songbook. To others, she’s a unique and important singer with a haunting tone that envelopes every lyric she delivers. Then there are those who know her as an interpreter, paraphrasing and sometimes fully reinventing music and elements from the worlds of jazz, pop, classical and more.

Overall, Barber is one of the most important forces in the evolving idiom of jazz, as demonstrated in each of her recordings, from her 1989 debut Split to her latest project Clique that’s set for release on Aug. 6.