Violin sighs give way to a harmonious chorus on “(O Death),” the funniest, shortest song on Ambassadors’ debut album, Litost. The ironically titled tune is so purposely not serious as to toss a lyrical red herring into the middle of a meditation on the afterlife: “O death, show me your teeth / For I’m trained in the art of dentistry!”

However absurd, Ambassadors’ comedy comes neither unintentionally nor without careful thought.

“It’s important to have a good sense of humor about everything that happens to you,” said front man Sam Harris. “I wrote that after everyone was on their way to recovery.”

Blind since birth, his brother Casey was working as a piano tuner when the Harrises committed to the band full-time in 2010 with friends Noah Feldshuh, guitarist, and Adam Levin, drummer.

Shortly thereafter, another of Casey Harris’ lifelong medical conditions necessitated a kidney transplant. Their mother, a cabaret and jazz singer, was the donor.

“We’re glad it turned out well,” Sam Harris said. “It’s hard for me to write songs about things that happen right then and there. It takes me two or three years to write about something, and write about it well.”

Having safely escaped into the medical clear, Ambassadors now are focused on touring — with a Tuesday stop at Cain’s Ballroom in Tulsa — to support their impressive debut disc.Litost pounds airy, cooing vocals; R&B beats; and pop string arrangements into a tribal, indie-rock mash that begs comparison to Givers and Local Natives, but Ambassadors’ ears are more attuned to alt-rock.

“The minute we feel like we’re starting to box ourselves in or turn into something that’s definable, we immediately try to veer away,” Harris said, explaining the polarity of influences. “That’s when we get into danger zone.”

Their love of disparate genres is evident by the impressive range of covers available for free download on Ambassadors’ blog:Nicki Minaj’s “Save Me,” Ginuwine’s “Pony,” LCD Soundsystem’s “Someone Great,” The Strokes’ “Is This It,” Björk’s “Hyperballad” — the list goes on.

“People love that shit,” Harris said. “We never want to do anything too straightforward.”