INXS guitarist Tim Farriss would really like to "collapse into a heap" back in Australia after the group wraps the North American leg of its Original Sin Tour in mid-August. But rest may be short-lived since, he says, the group is "in the throes of discussing" its next album -- and first set of new material since "Switch" in 2005.

"We're looking forward to writing and putting out some new material," the oldest of INXS' three Farriss brothers tells Billboard.com. "Everyone's got a billion songs up their sleeve. My brother Andrew has two arm's lengths ready to go. Once I get home after this North American tour, I'm going to present some songs. It's definitely beginning."

Andrew Farriss, INXS' chief songwriter with the late frontman Michael Hutchence, previously said that he "took a break from writing for a little while" but more recently started "to get a very strong sort of re-passion again for that idea." This can be partly attributed to working on the "Original Sin" all-star tribute album, on which the group recorded "reimaginations" of some of its hits with guests such as Train's Pat Monahan, Rob Thomas, John Mayer, Tricky and others.

"Sometimes I'll write sections of songs that are half complete or ideas that are half there or a quarter there... so there's always something around that we can build from," Andrew Farriss explains. "And the other guys in the band over the years have built some quite strong songwriting skill sets among themselves, so whatever comes in the future will likely be from them as well as myself."

The Farriss brothers full expect that J.D. Fortune, the Canadian singer who now fronts the band by dint of winning the 2005 TV reality show "Rock Star: INXS" and is back on the road with the group after a brief separation in 2010, will be on board for the new album as well.

"He's changed a lot," Tim Farriss says of Fortune, who sang on "Switch" and on the "Original Sin" version of "The Stairs." "When he first joined the ranks I think he was sort of lost in space. I don't think he quite realized what he was signing up for, and he took on all of the sort of things we used to do back in the '80s and went sort of haywire. I think know he understands he's part of a family and really appreciates that and wants to still be part of the family. He's thriving and he's trying his hardest to be part of that, and he's doing a great job. He's singing better then I've ever heard him sing, and singing songs he said he couldn't before. It's really kind of thrilling."

INXS wraps up the North American leg of The Original Sin Tour on Aug. 14 in Atlanta.