The Pixies’ 2004 reunion tour and subsequent live appearances through 2007 comprised one of alternative rock’s most surprising and successful second acts. The group hadn’t lost its gift for simmering music onstage, but as anybody who downloaded the Pixies’ first new song in more than a decade (the June 2004 single “Bam Thwok”) found out, the songwriting alchemy that made those old songs so indelible wasn’t as easy to relocate. So don’t expect a new Pixies album any time soon. But that isn’t such a bad thing when the group’s principle songwriter, Black Francis, and its heartthrob bassist, Kim Deal, the leader of the Breeders, continue to craft such fine albums for their current careers.

Mr. Francis’s “Svn Fngrs,” out today, and the Breeders’ new “Mountain Battles,” out April 8, showcase two artists perfectly at ease with life outside the Pixies. Black Francis is actually the Pixies stage name of Charles Michael Kittridge Thompson IV, who only started calling himself Frank Black in 1993 following the Pixies’ dissolution. In the 15 years since, he has steadily released 13 albums as Frank Black, until 2007’s “Bluefinger,” which was credited to Black Francis. The new 7-track EP “Svn Fngrs” is also a Black Francis release, and it helps clarify what the difference is between Mr. Black and Mr. Francis. Mr. Black, as witnessed on 1994’s “Teenager of the Year” through 2005’s “Honeycomb,” is the personality that explores everything from pure pop pleasure through Bob Dylan-tinged folk and country; Mr. Francis is the man who writes gnarled, almost decadent guitar rock slightly similar to the Pixies, but honed and polished by maturity. That’s not to imply that Mr. Francis has lost any of his dark flair for moody drama; he’s just much better at creating it now. “Svn Fngrs,” which features Mr. Francis on guitar and harmonica, backed by the bassist Violet Clark and drummer Jason Carter, filters the leader’s thorny rock through a power-trio format that suits his punchy but lovely songs.

Mr. Francis’s choppy guitar chords and serpentine lines define everything here. From the Kinks-y melody powering “Half Man” to the locomotive chug that makes “I Sent Away” sound a bit like X’s “Johnny Hit and Run Pauline,” Mr. Francis barely lets up on his music’s throttle over the album, which sprints by in a little more than 20 minutes. That adrenaline rush makes the album an effective pop-rock jolt, tempered by Mr. Francis’s gift for curlicue storytelling that coyly hides romantic themes behind blunt, pulpy song titles. A pealing guitar line introduces “Garbage Heap,” which the song describes as a burning pile located at the edge of town. Then Mr. Francis turns it into a Killers-like dark romance as the song’s narrator promises to stay at this heap with an unnamed person of affection. And “When They Come To Murder Me” starts out in a growling, defiant thrust of bragging murder rock, but Mr. Francis subverts it into a gimlet-eyed fugitive song.

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The Breeders have been Ms. Deal’s main songwriting venue since she formed the band in 1988 with Throwing Muses singer-guitarist Tonya Donelly. The band’s early albums, 1990’s “Pod” and 1993’s “Last Splash,” served as founding documents for the growing female-led indie punk rumbling out of the American underground at the time. And even though the band’s modest hits — “Iris,” “Saints,” “Divine Hammer,” and “Cannonball” — sounded like textbook independent rock, Ms. Deal has always let the Breeders follow wherever her songwriting muse wanted to go. With “Mountain Battles,” it winningly roams through familiar rock ‘n’ roll, pulsating electronic beats, abstract lullabies, subtle art rock, and even a glorious Spanish ballad.

It doesn’t feel a hodgepodgey, either. Since “Last Splash,” Ms. Deal’s twin sister, Kelley Deal, has been a key Breeders element, providing second guitar or bass to the band’s airy mettle. But more than that, her voice is ideal for harmonizing with her sister’s trademark angelic tone, which sounds as though it hasn’t aged a day since early Pixies albums.

Their voices certainly lift everything they sing together here. Musically, “Mountain Battles” is even more stripped down than the group’s last album, “Title TK,” which was essentially a lo-fi noiserock album. The new one is even more elemental, with songs hung on mere programmed beats and noises (the jaunty “Bang On,” the exotic “Istanbul”) or haunting guitar sounds that build into monolithic pulses (“No Way”). Throughout, the Deal sisters’ voices complement and play off each other, with Kim’s acting as the main attraction for most of the album.

Her familiar alto and gift for simple hooks still makes near-perfect indie rock. Lead track “Overglazed” is defiantly uncomplicated. Over anthem-like flourishes of boilerplate guitars, bass, and drums, Ms. Deal cries out, “I can feel it,” in her siren-like wail. What would sound like a cheeky joke in any other band’s hands becomes a catchy little intro for the Breeders.

“Walk It Off” appears about halfway through the album’s unfussy 36 minutes, and it’s the sort of immediately memorable song that Ms. Deal can craft in her sleep. A three-note bass line skips along to an easygoing drum pace, and Ms. Deal sings a casually funny song about being in a band and not always liking it.

“Walk It Off” is what old fans will love, but two of the best songs here are the result of the Deal sisters ditching their indie formula entirely. “Here No More” is a gorgeous country song that rides a strummed acoustic guitar and vaults into the stratosphere on the Deal sisters’ harmonizing; it sounds unmistakably like the Deals, but its sober sentimentality makes it feel like a forgotten gem from the 1930s. The seductive “Regalame Esta Noche” features Kelley Deal singing in Spanish with an easy-swaying guitar shimmy, sounding like surf music slowed to Don Ho speed. It shouldn’t work on any album, especially on one where it’s sandwiched between the plucky “Walk It Off” and the blithe “Here No More.” But “Regalame Esta Noche” may be the most beautifully weary love song from a band lousy with them.

Who cares about a new Pixies album? At this point, an all-Spanish Breeders release sounds like a much more rewarding treat.