The group, who are currently working on the follow-up to 2007's Minutes To Midnight, revealed that they always aim to create a unique sound.
"We make records as a challenge to ourselves. And the challenge this time is: 'Nobody else is making a record that sounds like this, only we can do it'," bandmember Mike Shinoda told MTV.
"It's been going great, I feel like it's an entirely different process and an entirely different style of music than anything we've done before."
Discussing the direction of the record, Shinoda said: "It's hard to place. People keep asking me, 'What does it sound like?' and it's hard to describe. When people hear it, they're going to have a tough time saying that it falls into a category.
"The album is going really well - we decided to go with Rick Rubin again, he's been in the studio with us.
"And we've been working in a different studio than we did the last record in, we decided to go back to the studio we did Hybrid Theory and Meteora in."
Lead singer Chester Bennington recently revealed that he battled alcoholism and considered suicide following the breakdown of his first marriage in 2005.