Aaron Harris doesn’t go around looking for ghosts. He isn’t a medium or a seer or a soothsayer or even—as he puts it—a “weird spiritual person.” But when he walked into the drum room of Bomb Shelter Studios, a converted 100-year-old soap factory, he knew something was in there. 

“It’s a really beautiful, really amazing studio,” Harris recalls, “and the drum room is huge—all-brick walls, high ceilings, concrete floors. I remember checking it out, and I just got this really weird feeling. I turned to the assistant who was kind of giving us a tour, and I was like, ‘Is this place haunted or anything?’ He said, ‘Yeah, it’s really funny you ask that because some weird stuff happens in here at night.’ And I thought, ‘All right, perfect. We’re recording here. This is definitely where we’ve got to do it.’ I don’t know what it was, but something definitely told me that that was the studio. It had this almost creepy feeling that felt really perfect for the vibe of the record.”

The almost-creepy-feeling record is In the Absence of Truth, the latest full-length from Harris’ post-rock, experi-metal band Isis. And if that vibe alone isn’t recommendation enough for you to check it out, well, let us be the first to smack you upside the head with this pronouncement: Absence is, sticks down, one of the year’s best discs, with over an hour of sophisticated, instrument-dense tunes that combine heavy guitars, trance atmospherics, clean and death-growl vocals, and tricky time signatures—all expertly born on the muscular back of Harris’ superb, tribal tom beats. These Isis dudes, to put it plain, can really, really play.

A little surprisingly, then, Harris himself has never had any formal instruction. “And I couldn’t even tell you honestly what some of the timings are in some of the stuff I’ve done over the years,” he says, apparently gifted with a strong internal clock and a knack for untangling twisted tunes. Harris in fact picked up most of his stick skills the old-fashioned way—by whacking the hell out of a drum set. Around age 12, he discovered his dad’s kit in the basement and started jamming along to Chad Smith and Bonham, eventually tackling songs by Soundgarden, Fugazi, Helmet, and the Melvins in high school cover bands. And when he was 18, after he had moved from Maine to Boston, and after his first serious band, Loga, had fizzled out, Harris’ penchant for progressive playing proved just what vocalist Aaron Turner and the rest of the Isis guys were looking for to forge a new sound. “We were all interested in forming a band,” Harris says, pausing for a second before adding a sentence that makes all the difference: “We had the same musical vision.”

Pay particular attention to that word vision, because unlike your typical chops-out-the-yin-yang group, just shredding tune after senseless tune, Isis specializes in composing unified high-concept albums. From 2000’s Celestial (with its critique of tower imagery in Western culture) to 2002’s Oceanic (whose main character explores the idea of community) to 2004’s Panopticon (again a take on the tower, this time by way of English philosopher Jeremy Bentham and French cultural theorist Michael Foucault), the band weaves thoughtful themes throughout its work, and the new album is no exception. Don’t get your Google fingers warmed up just yet, though, because you’re not going to find a quick, ready-to-digest summary of Absence. For this one, the band is holding back the crib sheets and the Cliff’s Notes. 

“This time around,” Harris explains, “we just all decided that with [the previous albums] we kind of hand fed the information to everybody. The whole point of doing these kinds of concept records is to get something to the listener to kind of get involved with, to make the record a little more personal. And when we throw [information] out there—here’s what this means, here’s what it is—it kind of defeats the purpose. So this time we wanted to leave a little more mystery for the listener to make your own ideas or concept or relationship with the record.” But Harris does offer one tantalizing hint, gleaned easily enough from the album title itself. “It’s based loosely on perception,” he says, “on personal perception of anything really, and what’s true and what’s not true.” 

It’s all heady stuff to be sure. But, mercifully, you don’t need a Ph.D. in comparative philological postmodernist philosophy to just sit back and enjoy Harris’ pounding. And this time, there’s a whole lot more pounding to enjoy. “I always had a less-is-more approach to my drumming,” Harris says, describing the repetitive, trance-inducing rhythms that have anchored the band’s sound on the last three releases. “But this time going into the record, I just felt kind of lost as far as direction and what I wanted to do, like I exhausted the approach I had on the past records. And I just didn’t want to dumb things down. I was interested in trying to do something kind of unconventional, where it didn’t have to be a kick/snare/hi-hat beat, you know? It could be a tom beat or whatever I felt fit. I just wanted to try some new things.” 

So Harris let himself bang out more complex beats, still repetitive and trance inducing, but heavy on the toms for a rich tribal sound. He also added to his (get ready for this) minimal 4-piece kit a double pedal, which you can hear put to stomping good use on the album’s closer, “Garden of Light.” And for the first time, he even got plugged in, hooking up a Roland SPD-10 and a couple of Madala pads (the kind Danny Carey uses) for triggering organ and tabla sounds on songs like “One Thousand Shards” and “Not in Rivers, But in Drops.” He did all of this, mind you, while still effortlessly navigating the band through the usual number of tripping and treacherous time signatures.

Did all that extra effort have anything to with the ghost? “No,” Harris laughs, “it was just that one day that I felt something. When I went back to do the record, it didn’t feel like that at all to me.” Maybe that’s because the supernatural got spooked by all the super sweaty drumming. 

“It was a lot of hard work,” Harris admits. “[The album] put everybody in a position where they were trying and playing things that we’ve never done before, and just really pushing ourselves. So I can very comfortably say that I think this is our best work, and as a drummer, definitely my best work. I’m really, really psyched on it.”