Bettye LaVette appears on the cover of her new memoir the way her admirers often see her in concert. Which is to say at the mercy of her emotions. Her eyes are closed, head tilted back. Her mouth is twisted in a look of anguish. The muscles around her throat are clenched, as are her fists. She’s standing in front of a classic old microphone.

For a static image, it conveys a lot about LaVette, 66. a soul singer who first emerged in the early 1960s but didn’t find lasting fame until 40 years later. In 2005, Anti-Records, an indie label in Los Angeles, released “I’ve Got My Own Hell to Raise,” which unearthed LaVette from years of relative obscurity and prompted generations of new fans to wonder, “Who is this — and why didn’t I know about her sooner?”