Hey all, quick introduction. My name is Elmo Arteaga and I work at Lambesis Studios with Daniel Castleman (Impending Doom, Carnifex, As I Lay Dying). I personally asked Daniel a bunch of questions based off the Impending Doom albums he's done because I aboslutely LOVE the quality of his recordings (especially TWBV). Firstly, I'd like to note that the drums were recorded live at Signature Sound Studios; Studio A in San Diego,CA, and everything else at Lambesis Studios in Escondido, CA. Daniel does NOT use any amp sim software, he strictly mics amps. For those records he told me he used a tubescreamer to a 6505+ through a hand-picked mesa oversize recto cab with an sm57 and MD421 pointed at where the cone meets the cap (as of this moment, I'm unsure about the 421, I will double check and edit this post, I thoroughly apologize).
Daniel's way of mixing drums is that he likes to blend SINGLE samples into a live recording. He doesn't use multiple samples like SSD or others like that, nor does he use drumagog! He tabs-to-transient then pastes his one-sample-per-voice addition and moves to the next transient. He will then velocity automate any rolls. Although you can hear that absurd machine gun effect on the first track off TWBV, you can't deny that the remainder of the albums drums sound so clear and pristine.