Shemekia Copeland is a volcano of blues-drenched soul. She spews it, spouts it, erupts with it. She is a force of nature. Her voice—a stone classic shout that also has subtler colors when necessary—is a lava flow. She’s on fire.

The Soul Truth is album four from the daughter Texas blues legend Johnny Copeland, and it’s near perfect. Pumped up from below by a lean ‘n’ mean Memphis-style band led by producer and guitarist Steve Cropper, Ms. Copeland delivers a dozen vintage-sounding thick slices of soul pie. It’s not throwback music—no obvious covers and mostly original tunes—but it is pure soul music from the tight American tradition. With the Muscle Shoal horn section punching out hip and hard lines, with Cropper stinging the tracks with plucked power, with Chuck Leavell playing classic R&B piano, and with the whole band so tight you could bounce a blackberry off its groove and hit the moon, nothing can go wrong here.

But the best band in the world won’t matter if the lead singer can’t push the lyrics and the sweetly bent notes over every rooftop. But Ms. Copeland has got the horsepower and then some. On bluesy ballads like “Strong Enough”, she never shouts but owns every syllable because she sings the lyric and not just the melody. She growls when it makes sense, and she slides up to the higher notes and into a vibrato as wet as a ripe peach. On a ballad, the quieter she gets, well, the mightier the whole performance.

But on most of the tunes, Shemekia is up-tempo and very nearly over the top. She rocks like a fresh, young Tina Turner, putting enough swagger in each note to embarrass almost every lead singer working today on the seven continents. The opener, “Breakin’ Out” is among the most blues-oriented tunes, and Ms. Copeland seems to go nearly sharp on the key notes. But her sound is ripe rather than off, and it matches the lyrics perfectly, as she sings about “makin’ my escape” from a bad marriage. This is music of swagger and liberation. “Life with you is worse, worse than any jail. Each night I dream of bein’ free—I’m breakin’ out!”

Shemekia, we want to come with you.

On one track, Ms. Copeland asks for and attempts the impossible. Wondering “Who Stole My Radio?”, Shemekia laments the sorry state of the airwaves. “I want passion! I want feeling! I want to be rocked from the floor up to the ceiling!” Shemekia is a detective hunting for what’s missing these days. “Who stole the funk? Who stole the soul? Who took the rock out of rock ‘n’ roll?” The solution, as Ms. Copeland well knows, is to get some of her stuff on the radio. Talk about something that makes you want to put the top down and twist the volume knob. The tune feels so right that you can nearly imagine the day arriving at last.

And on track after track after that, you keep wondering, “Why couldn’t radio stations play this, man?” They played Aretha on the radio, so why not the sweet soul lament of “Poor, Poor Excuse”? The strut of romantic complaint in “All About You” is not only half of a couple’s argument but also a dead-on description of the typical hip-hop mogul. “Used” is as haunting a ballad as the radio today knows—like a slice of indie-rock or track of folk-pop that (is it possible?) is well sung in addition to being well felt. C’mon, Mr. DJ!

But does it all sound too old-fashioned, too Stax-y or Queen of Soul? It’s hard to say. Ms. Copeland was born in 1979 in Harlem—she’s hardly out of touch with today’s reality. On the other hand, she doesn’t have much feel for the gloss or surface that largely defines today’s pop radio. But she knows that, and she’s OK with it. On the album’s last track, “Something Heavy”, Shemekia Copeland sings with only acoustic guitar accompaniment, making what amounts to a low-fi joke of her weight. “I need something heavy—I got to get some satisfaction. It might be a steak well done. Sometimes I got to go for a ten-mile run. The whole world is at my door every time I gain a little bit more.”

Shemekia Copeland knows that pop music needs her, but she’s also too wise to think that she’s the next Britney or J-Lo. I haven’t heard her yet on “Hot 97” or “Q102”. But you don’t have to listen to the radio. You can pick up The Soul Truth and spin your own greatest hits.