Before work could start on the album, the band faced more difficulty—the departure of its longtime bassist Josh Fauver—which made Cox fear the band would break up.
It did not, but Cox still wound up playing a melodic bass line on "Punk" during recording sessions earlier this year. The reason for the extra duties wasn't personnel-related.
"I played a lot of stuff on that song, but that's only because the demo is so confusing because I was drunk when I made it," he said during an interview at his house in Atlanta. "I was in character for that song."
The smoldering, propulsive track was part of a burst of songwriting within the past two years that Cox says resulted from "very dark" things that he declined to explain further. These songs form the bulk of "Monomania," the band's fifth full-length album due to be released on May 7.
Anticipation for the album was goosed by a performance of the noisy title track in early April on "Late Night With Jimmy Fallon," which was analyzed on more than a dozen music blogs under headlines describing it as "brilliant, bizarre.
Cox, who turns 31 on May 15, said the band had been doing all-night rehearsals to prepare for a string of tour dates around the Southeast before they head to Europe for club shows and festivals. The day of the interview, they'd practiced until 7 a.m.
"I sleep all day. That's what I do," he said. "I'm like a bat."
The new album is a collage of elements familiar to Deerhunter fans—cacophony interspersed with tunefulness, guitar tones that range from scratchy to soothing and vocals that occasionally dissolve into distortion. While the first half of the album challenges listeners with the rawness of several tracks (including the intriguing "Leather Jacket II"), Side 2 features some of the band's jauntiest offerings yet.
Despite a band news release describing the new album as "nocturnal garage," Cox said the intent wasn't to make it sound any different from the band's other records, though he calls it "much more of an electric rock record" than the dreamier "Halcyon Digest.
By the time the band began planning for recording sessions, Cox had hundreds of demos for them to choose from. During the interview, he said there are more than 600 on his hard drive.
Then came Fauver's departure. Guitarist Lockett Pundt and drummer Moses Archuleta, he said, were in favor of continuing.
"We were all talking about getting together to work on the new stuff, and then he just sort of dropped that on us," Cox said, adding that Fauver cited personal reasons. "I honestly thought when Josh quit, 'Oh well, I guess that's that.' But then I realized, 'What am I going to do with all these songs?'" Cox said.
By January, photos surfaced of new bassist Josh McKay and new guitarist Frankie Broyles strumming their instruments at the band's Notown rehearsal space and studio in the Atlanta area. Cox describes the space as "our bat cave," where he often goes in the middle of the night to record ideas for songs.
The band then spent a couple weeks listening to Cox's demos and decided together which ones they wanted to put on "Monomania." Recording sessions for the album were held in New York in January and February.
"Some of my favorites didn't make it on the album. Some songs that I didn't really think were worthy did make it on the album. Some songs that we all thought were the best ones didn't make it on the album. I don't know how that works," he said.
Asked whether the castoffs might surface someday, Cox replied: "I mean, one would think so, but I'll probably start writing other songs. That's how it happens. That's how you have 600 songs."
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