It’s not unusual for an indie-rock outfit to expand its membership to allow for ornate flourishes of strings, brass and coed vocals. You could start with Arcade Fire or Sufjan Stevens, examples that Typhoon’s Kyle Morton took to heart in building his own band. But as a recording and touring unit of 11 members, Typhoon whips up a uniquely sizable storm.

It all began when singer/songwriter Morton and a few of his future bandmates were growing up in Salem, Ore., balancing dual musical lives in school choirs and jazz bands by day and punk groups by night.

“About the time of going to college, I had the idea to conglomerate these two things,” says Morton, 28. “[Then] it started to snowball.”

Typhoon eventually settled into their current lineup, which includes two drummers, two violinists and three horn players. Yet the Portland-based group doesn’t sound overcrowded. “The trickiest and most rewarding part of working with the large ensemble is preserving space,” Morton says. “When I write, and when we go to arrange, it’s by process of subtraction. We’ll try everything and then we start stripping away.”

That’s what often happens in the studio, the way it did with Typhoon’s 2013 album White Lighter, only to be restructured for the stage. “This is so not sexy,” Morton prefaces, before explaining that drummer Pieter Hilton “came up with this spreadsheet that basically had all the parts in the songs, all the members in the band, and who was playing what parts, and who conclusively had a free hand to do something.” As a result, to play “Young Fathers” live, trumpeter Ryan McAlpin was free to hit snare rimshots.

“I cast myself as the main editor,” says Morton, who plays guitar and keyboard. In writing, he says, “I’ll have a melody and think it needs to be played by horns, or I’ll get really focused on the beats. I used to play drums more. Now I have more fun kinda playing drums through our actual drummers. Once I sit down with the other people in the band, it usually gets a lot better, a lot more interesting, because that’s their craft.”

What Morton may contribute most, however, are darkly abstract yet emotive lyrics. “I tend to get most of my ideas and inspirations from literature and, to some extent, from philosophy,” he says. “Music being what I’m comfortable with, that’s where I bring those ideas to bear.”

Apart from Kafka, Nabokov and Kierkegaard, Morton drew much of his personal philosophy from a teenage battle with Lyme disease. “All the physical complications pale in comparison to how it formed my psychological perspective,” says Morton, who was bitten by a tick at age 12 and underwent a kidney transplant as the illness ravaged his body. “It set off a spiral of events that would change my life, but it’s all mashed in with a lot of other messy things. It’s hard for me to piece out the sickness from just getting older and relationships straining.”

As such, Morton’s lyrics seem to make specific reference to his medical ordeal. “Common Sentiments” closes with the mantra “I will be good though my body be broken,” and in “The Lake,” Morton sings, “The grass grew tall where it met the lake / There was a different bug must have bit my leg, though I never saw it.” Yet there’s another narrative at work there. “I was in love, and this person wanted somebody else,” he says, “so my sickness became wrapped up in this other love-sickness.”

Ultimately, however, Morton’s lyrics find uplift in the hopeful sweep of Typhoon’s sparse orchestration. “Sometimes I try to do what Stephin Merritt of the Magnetic Fields does really well, pairing dark subject matter with lighter music,” Morton says, though he credits his bandmates for a bigger influence.

“We keep each other going,” he says. “I don’t think any one of us would do this if we weren’t all in. It’s consolation for all the dark stuff. That’s not my design, but I’m very grateful for it.”