They did for 2 songs on Cosmogenesis. The title track was one of them, can't remember the other off the top of my head. Christian was the only one who used it on the album. They both told me that there was going to be a lot more 7 string on the new album. I'm looking forward to it.I don't believe they did on the current or previous album. I'm pretty sure they will be on the next though.