Editor’s Note: In Sound Advice, veteran NEWS entertainment writer Dale McGarrigle, rock columnist Emily Burnham and a revolving stable of NEWS writers review new albums from across the musical spectrum.

Sigur Ros

“Hvarf/Heim” (XL Recordings)

Iceland’s Sigur Ros don’t merely make great music. They create a beautiful, self-contained world in their songs which can’t be replicated by any other band on earth.

The falsetto coos of singer Jonsi Birgisson, sung in Icelandic and sometimes “Hopelandic,” Birgisson’s very own invented language, combine with the band’s towering orchestral crescendos to form a wall of sound that envelops the listener.

Sigur Ros’ last album, 2005’s “Takk,” improved on the band’s already impressive formula by adding a bit more of a rock crunch to its usual flowing, classical-style compositions. The group’s latest release, “Hvarf/Heim,” is a two-CD set, with one disc containing older, previously unreleased songs the band has recently reworked while the other offers acoustic versions of songs from their four previous studio albums.

The reworked songs on the “Hvarf” disc continue in the vein of “Takk,” elaborate orchestral pieces with more of a rock edge than Sigur Ros’ earlier material. “Hliomalind” is an actual, honest-to-goodness Sigur Ros rock anthem, with a shout-along chorus and chiming guitar work. A new version of “Von” from their first album extends the song to a blissful nine-minute epic, while the frantic marching band conclusion of “Hafsol” is one of the most unhinged and breathtaking moments in Sigur Ros’ entire catalog.

The acoustic versions of some of the band’s best-loved songs on the “Heim” disc are also a revelation, with favorites like “Staralfur” and “Vaka” maintaining their otherworldly beauty despite being stripped of Sigur Ros’ trademark bowed guitar, a constant, droning presence on all of its albums.

What would be considered a stopgap release between studio albums for most bands is turned into an indispensable part of Sigur Ros’ history by the sheer power of the music. “Hvarf/Heim” is a testament to the raw talent of one of the most unique and important bands of our time. – TRAVIS GASS

Various artists

“I’m Not There: Original Soundtrack” (Columbia)

Director Todd Haynes’ forthcoming Bob Dylan biopic, “I’m Not There,” features the man as portrayed by seven different actors and actresses – everyone from Richard Gere to Cate Blanchett – in vignettes focusing on different times and aspects of his career. The accompanying soundtrack, naturally, draws from nearly every album in the Dylan catalog, and features a veritable who’s who of rock, folk and indie bands and songwriters, offering their takes on both the big hits and more obscure tracks.

For example, the unofficial “house band” of the soundtrack, Million Dollar Bashers, is comprised of Lee Ranaldo and Steve Shelley of Sonic Youth, jazz organist John Medeski, guitar god Nels Cline and punk legend Tom Verlaine, among others. They accompany indie rock royalty such as Stephen Malkmus, who offers a faithful take on “Ballad of a Thin Man” and a rollicking version of “Maggies’ Farm.” They’re less successful with Eddie Vedder, who gives a tepid reading of “All Along the Watchtower,” and with the Yeah Yeah Yeahs’ Karen O, who sounds like she’s covering PJ Harvey’s version of “Highway 61 Revisited,” rather than the actual Dylan song.

The other band prominently featured is Calexico, who mix their sprawling desert rock with the likes of Willie Nelson, Iron and Wine and Roger McGuinn, all three of which give some of the most memorable covers on the disc. Iron and Wine takes on the sensual “Dark Eyes,” a song from the largely forgotten 1985 album “Empire Burlesque,” while mariachi horns and pedal steel decorate McGuinn’s version of “One More Cup of Coffee” and Nelson’s sad, thoughtful performance of “Senor (Tales of Yankee Power).”

Some songs are welcome surprises, such as Jack Johnson’s cozy, romantic “Mama You Been On My Mind” and the Black Keys’ lo-fi fuzz blues take on “The Wicked Messenger.” Dylan contemporaries like Richie Havens and Ramblin’ Jack Elliott even show up, with versions of “Tombstone Blues” and “Just Like Tom Thumb’s Blues,” respectively. Are there any other songwriters with as diverse a songbook as Bob Dylan, with songs as open to interpretation? That’s the beauty of his music: it transcends itself, and it’s context, and simply speaks for itself. – EMILY BURNHAM

Various artists

“City of Dreams – A Collection of New Orleans Music” (Rounder)

This four-disc collection is nothing short of a party in a box-set. Roll up the rug and push back the chairs, fill the wash basin with beer bottles and ice, invite the neighbors over and turn up these tunes.

Musicologists could bore you with the history of New Orleans music and its impact on other forms – French, African and English cultures collided in a steamy, exotic setting; the Mississippi River carried the Delta sound north to Chicago, where the urban influence morphed it into the blues and later, rock ‘n’ roll. Instead, just listen to this fat and juicy slice of the Big Easy and you’ll get it.

The songs included here are culled from Boston-based Rounder Record artists – not a label that comes to mind when thinking of New Orleans, but one that values musical traditions. Rounder began signing and recording artists in New Orleans in 1981, so most of the songs are from the last 25 years, but the label also purchased two small local record companies, and included here are cuts from the 1950s and 1960s which Rounder inherited with the acquisitions.

Artists include Irma Thomas, Professor Longhair, Art Neville, Champion Jack Dupree, Solomon Burke, Ruth Brown, and the Dirty Dozen Brass Band, among many others.

The four discs are organized under the loose headings, “Big Easy Blues,” “Street Beat,” “Funky New Orleans,” and “Every Emperors.” The first disc showcases singers in the classic New Orleans R&B style; the second features music inspired by the African drum marching bands; disc three features the city’s signature syncopated bass and drum music; and the fourth disc is loaded with piano music.

Most of the songs are short, but punchy, funky, spicy, soulful and irresistible, the perfect antidote to a long Maine winter. – TOM GROENING

“Brave” (Epic)

Jennifer Lopez

It’s not easy being a multimedia hyphenate.

I mean, top-selling recording artist, acclaimed movie star, fashion-industry entrepreneur. Imagine how good J-Lo could be if she focused on one thing.

She’s got a built-in audience for her music out there. When her first all-Spanish language album “Como Ama una Mujer” was released in March, it went straight to No. 1 on Billboard’s Latin Album chart. With Hispanics the largest minority in this country, that’s a great base from which to build.

Lopez’s last English-language studio album “Rebirth” came out in 2005, but it seems longer ago than that. Maybe that’s because J-Lo the celebrity has been so prominent, getting married (again), this time to rico suave Marc Anthony, and now on her way to motherhood (that worked so well for Britney).

“Brave” is Lopez’s first studio album not to debut in the Top 10 of the Billboard Album chart, so perhaps she stayed away too long from a crowded marketplace.

Still the album hearkens back to Lopez’s earlier releases, full of danceable pop, hip-hop and funk, overseen by producers such as Lopez recruited producers such as J.R. Rotem, Bloodshy, Midi Mafia and Ryan Tedder. Fortunately, Lopez remembers her roots, and doesn’t feel the need to inflict an album of standards or covers on her fans in a misguided attempt to “grow.”

Although younger pop princesses have moved in on her territory over the past decade, Lopez still knows how to turn out memorable tunes such as the single “Do It Well,” “Mile in These Shoes,” “The Way It Is” and the title cut. Instead of the fashionable rap on every song, she instead sprinkles in well-chosen samples from classic R&B songs by Tavares, Eddie Kendricks, Michael Jackson, Great Pride and Bill Withers.

The result is a memorable mix of new and old, which is a “Brave” thing to do in today’s cookie-cutter pop-music world. – DALE MCGARRIGLE