One Direction have made a shift on 'Midnight Memories.' They have stepped away --a bit-- from the frothy teen pop of 'Up All Night' and 'Take Me Home' in favor of songs with more instrumentation, piled with layers of richer vocal harmonies and lots of acoustic guitar.

Their friendship with Ed Sheeran, who penned their hit 'Little Things,' is rearing its head by showing its influence in their music.

But the result is fantastic. It's a believable change and not drastic, and it's One Direction's first post-teen pop album. They co-wrote most of the songs and experiment with neo-folk, singer-songwriter fare and even classic and glam rock. Niall Horan plays guitar and his love of rock is apparent on many of these songs.

There are lots of layered harmonies and gang vocals that invite singing along.

The album is largely stripped of bubblegum pop, but saccharine harmonies are still there, settling in seamlessly next to acoustic strumming and glam rock riffs. The album is a turning point and marks the evolution of 1D, extending their career.

1. 'Best Song Ever'
The album opener was the first taste we heard of the album and it's the fun, frothy, uber catchy pop that the boys have become known for. It's full of "whoa oh ohs." Oh and the intro nods to The Who's 'Baba O'Riley.' [Listen to the Song]

2. 'Story of My Life'
One Direction show off their Mumford + Sons side here. It's boy band folk, more aligned with their Sheeran-penned 'Little Things' from 'Take Me Home.' 'Story of My Life' is a full-bodied song, with Harry Styles asserting himself as the vocal star of this track. [Watch the Video]

3. 'Diana'
1D revert to the '80s with their neo take on new wave. Of course we think of Princess Di, the patron saint of the U.K. It has a very '80s pop feel, with a nervously tense, propulsive beat.

4. 'Midnight Memories'
The boys hinted at rock 'n' roll with the intro of 'Best Song Ever.' But they fully indulge it here, in this riffy, anthemic jam with stadium-sized hooks. Who knew 1D had such a rock jones?!

5. 'You and I'
No, it's not a Lady Gaga cover. But 'You and I' also falls in line with 'Little Things.' It's a romantic ballad whose words are accompanied by acoustic guitar work. It's delicate and vulnerable, and when Verse 2's harmonies come in, our knees got weak. Swoon x 5.

6. 'Don’t Forget Where You Belong'
Is it us, or are there voices just better and stronger with each album? This introspective song, contemplating life on the road and their station in life, is sincere as it gets.

7. 'Strong'
This Liam Payne-led song is not as frothy, and again demonstrates that the band's developing a mature sound. We're hearing One Direction the vocalists, as opposed to One Direction the boy band. It sorta reminds us of the Wanted's foray into 'We Own the Night.' Don't shoot us for comparing the two.

8. 'Happily'
'Happily' is a robust, acoustic-guitar backed track with gang vocals that beg you to clap and sing along to 'em. When the boys sing "We're on fire now," we want to burn alongside them. It's another mini-Mumford track, with the guitars and harmonized bro vocals. It's 1D's stab at neo-folk. It's not much different than what Avicii did with 'Wake Me Up.'

9. 'Right Now'
Harmonies! Falsetto! "Woah oh oh" choruses. Lyrics that will make Directioners swoon, like "Right now / I wish you were here with me / Because right now / Everything is new to me." Those are the elements of 'Right Now.' Hey, guys, did you know that Harry and Zayn and Louis and Niall and Liam can actually sing?

10. 'Little Black Dress'
Whoa, what's this? One Direction going glam rock? Get ready to play some air guitar, as the monster riffs that grind in the intro of the toe-tapping 'Little Black Dress' remind us a bit of Stone Temple Pilots, while the song is front-loaded with vocal harmonies. Not one member asserts vocal dominance. It's a total team effort. It's one of the best on the record, too.

11. 'Through the Dark'
More toe-tapper, Mumford-like, campfire-ready neo-folk asserts itself on 'Through the Dark.' Phillip Phillips, John Mayer and the twice aforementioned Sheeran traffic in this sound, and 1D haven't just dipped their toes into this pool. They dive right in, head first, and it works, since their voices are so varied. When they sing, "I would carry you over / Fire and water," we melted. Again.

12. 'Something Great'
How could anyone remain upright when listening to a song like this? It makes you want to fall backwards into your bed and let it envelope you.

13. 'Little White Lies'
'80s pop lives on 'Little White Lies,' complete with more of those charged rock guitars. The a cappella opening reminds us of the power pop tracks that dominated the decade. The tense, heartbeat-like drum beat and the boys' vulnerable lyrical declarations reveal that not even 1D are immune to a sneaky bad girl who likes to break hearts. Boo! Hiss! on her.

14. 'Better Than Words'
More rock from 1D. It's clearly a guitar-dominated album and we're not complaining. Evolve or die, right? It's a love song about her making the boys weak in the knees. A sugary, addictive harmony anchors the song, too. 'Midnight Memories' gets better as the album progresses. By track 14, we're still as alert as a watchdog and remain interested in what they are doing.

Deluxe Edition Tracks

15. 'Why Don’t We Go There'
This is more familiar 1D fare, with a little bit of an urgent, indie rock guitar riff. Wherever 1D invite us, we're going along for the ride, blindly.

16. 'Does He Know'
Is it us or does this song's melody sound a lot like the melody from Rick Springfield's 'Jessie's Girl?' Oh yeah, it's totally an homage. The rest of the song has a pop-punk buoyancy and energy. 'Does He Know' is another track that harks back to "early" 1D.

17. 'Alive'
Another raw rocker, with a bit of a glammy, punk, Sunset Strip vibe. We could picture 1D singing this in an update of 'Rock of Ages.' It has such an '80s pop-metal vibe, and it's as dirty as it is glitzy. Lovin' this anthem.

18. 'Half a Heart'
The boys end the deluxe edition with a heart-on-the-sleeve ballad that finds them feeling like they are half-men without the one they love. They croon, we swoon. The melody sounds like something on a Celine Dion record.