A few months back, we learned that  had begun working on their fourth album.  Now, guitarist Mark Tremonti is spilling some details about the record.

In a new interview with Music Radar, he talked about the mood of the album. "I don't think it's as dark as [our last album] 'AB III,' but listening to it, a lot of the lyrics are still on the darker side of things. But there's definitely a few uplifting concepts and themes on there as well. There's apocalyptic lyrics… all kinds of moods."

Tremonti says the album, due in September, is very high-energy, and thinks it will translate well live. The record is being produced by Michael "Elvis" Baskette, who also worked with Alter Bridge on their previous two albums.

Last year, Tremonti debuted his solo band, in which he is both the guitarist and singer. He reveals he also sings lead on one of the songs on the upcoming Alter Bridge disc.

"Elvis told me that Myles [Kennedy] wasn't really connecting with one of the songs and they started talking about me giving it a go. Elvis said, 'Let's take a negative and give you a chance to take that song that he's not feeling and sing it.' So I wrote it about a fictional apocalypse. Right now it's called 'The Waters Rise' and I'm glad to be able to have done it."

Alter Bridge will play one special U.S. show in October, with the venue and date to be announced on Monday (July 22). They'll then head to Europe for a headlining tour with Shinedown and Halestorm.