Alex and Sierra are gearing up to release their debut album, It's About Us, on Oct. 7 and the X Factor USA alums have been giving away tidbits.

Alex & Sierra Perform Just Kids At The Beach

On Thursday, they took to Twitter to announce that a somber new tune is coming very soon.

"Only a few more days til the new song comes out! it's simple and sad... if you're into that kinda stuff," they wrote.

Alex & Sierra Attend The Teen Choice Awards

The season 3 winners already released the album's lead single, Scarecrow, in May and its follow-up, Little Do You Know, in July. Recently, Alex and Sierra also put out the fun track Just Kids.

The two have been in the studio with some big names. For example, they worked with Grammy Award winner John Legend on a "really good song" a day before he was to perform at the Grammys in January.

"It was actually a really cool experience to write and meet someone who is about to perform on the Grammys but he's just a normal dude," Sierra said during a recent interview with Yahoo Music. "He's really nice and it was fun to write with him."

The song, however, won't be on their forthcoming debut, but it will eventually be released.

The couple also wrote Scarecrow with Martin Johnson from the band Boys Like Girls. They were even invited to Jason Mraz's house for a weekend and wrote with the singer, whom they spoke very highly of.

Alex and Sierra also told Yahoo Music that they went to writing camp to pen songs for their upcoming album, including All For You.

"We wrote 20 songs in five days," Alex said. "It just happened really naturally," Sierra added.

Fans can pre-order the album on iTunes.

It’s About Us tracklist:

1) Scarecrow
2) Give Me Something
3) Bumper Cars
4) Almost Home
5) Here We Go
6) It’s About Us (Interlude)
7) Little Do You Know
8) Cheating
9) Just Kids
10) I Love You
11) Broken Frame
12) Back To You
13) All For You