Three hot bands, two large mammals, and one cannibalistic instrument converged at the Casbah last Tuesday night, when Freelance Whales, Bear in Heaven, and Cymbals Eat Guitars swung through to represent New York City.

Elbow room was nonexistent by the time Freelance Whales finished setting up their bewildering array of instruments, which included a banjo, glockenspiel, and a harmonium to accompany the standard guitar/drum/synth setup. We knew we were dealing with some serious music geeks when the guitarist brought out a violin bow to stroke out minty-fresh sine waves for the glockenspiel to dance upon. Singer/multi-instrumentalist Doris Cellar, wearing cropped Tegan/Sara hair and a bird shirt (is bird the new wolf?), was adorable as she cracked nervous jokes with the crowd. Halfway through, they brought out one more instrument for good measure — an electric mandolin — and it felt like the scene near the end of “Revenge of the Nerds” when Poindexter plugs in his violin, spikes up his hair, and brings down the house.

Freelance Whales wrapped it up with their catchy single “Generator – 2nd floor,” which sounds like the Postal Service delivering a message from Sufjan Stevens. I’ve listened to this song about ninety times in the last two weeks, and if it hasn’t already been picked up for a car/iPod commercial, it’s only a matter of time. (If anyone on Madison Avenue is reading, please mail your checks c/o Owl and Bear for this juicy tip.)

Bear in Heaven’s look brought a slacker-cool to counter Freelance Whale’s affable band-geek. Throughout the set, vocalist Jon Philpot smiled graciously underneath a rad handlebar ‘stache, while cranking out buzzing, otherworldly electropop. They do have recognizable instruments, and you can even broadly match up fingering with the notes, but generally it’s impossible to tell which instrument — or planet — is responsible for the mesmerizing Flash Gordon tones. Not to mention the vocal effects, which modulated Philpot’s voice such that it could be mistaken for Jefferson Airplane singing miles away on a hilltop. Or maybe a hamster, except in space — a Space Hamster.

For the most part Bear in Heaven had my head bobbing, like during the bouncing monosyllabic verse of “Dust Cloud,” or the retro 80s chorus of “You Do You,” though occasionally they strayed from tonal melodies and lost my interest, and I’d start toward the patio for a second-hand smoke break. But then grizzly, bearded drummer Joe Stickney would explode into a tribal drum break, or a soft, throbbing pulse bombarded with sonic lasers, and I would get sucked right back in. I wasn’t the only one into it — there was also That Guy in the crowd with his arms up dancing the whole time. He’s the type of guy you typically love to watch, as long as he’s not douching it up right in front of you.

Cymbals Eat Guitars gave us a gentle reminder to put in our earplugs and came on loud, opening with “And the Hazy Sea,” the best single off of their debut Why Are There Mountains. Starkly contrasting the mellow vibes of the opening bands, Cymbals Eat Guitars brought workhorse garage rock, often dropping down to sputtering keys before blowing the lid off a screaming chorus. This maneuver kept triggering a certain superfan into epileptic, fist-flailing frenzies that clearly mortified his girlfriend but otherwise went unnoticed. The audience was much sparser and younger by this time, the earlier risers and weaker-stomached having disappeared hours ago.

They throw down some noisy guitars, but Cymbals Eat Guitars can still find their way around a hook. The show is high energy, with frontman Joseph Ferocious spraying sweat and spittle, splashing more fluids on the front row than GWAR. At their best, there’s a lot of Pavement to be found in their sound; at other times you don’t know if you’re on a chorus or a bridge, or if there’s any structure to the songs at all. But when Ferocious is bent over his axe, shaking his best O-face behind clouds of saliva and breaking strings as he bangs out one rocking burst after another, you don’t really care.