It is around 5:30 p.m. on a raw night in Cambridge's Central Square. The commuters are streaming through and the local weirdo shift change is in full swing, as the daytime crew relinquishes their benches and positions at the bus stop to the night shift of strange people. Everyone seems to be streaming through the square, but Emeen Zarookian appears to be moving in, having parked his Ford Focus - full of musical odds and ends. His vehicle, full of gear, is a percussion instrument unto itself, greeting every bump in the road with a chorus of tambourines and sleigh bells.

Zarookian has already had a hell of a day, waking up with what felt like a cold and self-medicating with different variants of lemon, honey and teas. He has already been through a rush-hour journey from Somerville, Mass., to his practice space in Watertown (to pick up the aforementioned car-full of gear) and somehow made it back to the heart of Cambridge for a 5:30 p.m. load-in at T.T. the Bear's. Emeen Zarookian is the nucleus of Spirit Kid, and it's Spirit Kid's record release show tonight.

Spirit Kid currently has a revolving membership that can slip into the smallest corner stage as a three-piece, but can easily fill a stage with guitars, keyboards and auxiliary percussion. He has a weakness that borders on fetish for auxiliary percussion. "It's like all the Beach Boys/Phil Spector recordings with tons of percussion melding with the drums so you don't even know what exactly you're hearing," he says almost lustfully, his eyes dancing with visions of tambourines, glockenspiels and other pieces of percussive paraphernalia.

While the band is now based in the Northeast, Zarookian's "Spirit-quest" started almost five years ago in Los Angeles, with a few songs and a grump next door that didn't seem to be a fan. "I had a terrible neighbor who would always complain to the building security that I was too loud every time I tried to record music," says Zarookian of Spirit Kid's first (and rare) critic. Luckily, he did not take the criticism to heart, even though the same neighbor didn't seem to mind him listening to music at the same volume.

Zarookian recorded under threat of building security, placing his guitar amplifier under a makeshift sound-baffle (aka cardboard box), and conspiratorially sing-whispering his vocals over the box-amped guitar and electronic drums. That first recording survived several translations and reinterpretations to become track nine on the record-to-be released tonight, Assumed By You.

In late 2006 Zarookian moved back to Boston, recording a series of tracks in his mother's basement and releasing them to his friends as "Emeen in the Basement." Zarookian admits that some of the initial recordings were pretty "weird and distorted." However, the groundwork for Spirit Kid began by coupling his intense thoughts and feelings and expressing them in a poppy, harmony-laden style more informed by the Beach Boys and the Beatles than the melodramatic emo stylings of many of his contemporaries.

Zarookian went through the music scene as a utility player in several well-known bands. He played a little bit of everything in the Age Rings ensemble and dabbled onstage with local soul sensation Eli "Paperboy" Reed, to name a notable few. He has lately been seen as a major founding member of the Sterns. Spirit Kid is all Zarookian - with a little help from his friends - and this arrangement has enabled him to enjoy all of the benefits of being a solo act as well as having a full band. "The nice thing about a solo project is the lack of drama," he smiles, before stressing, "I hate drama. I can't stand it!" Though logistical concerns become null and void with a one-man act, "It's pretty much a panic attack waiting to happen," says the man behind the Kid.

Spirit Kid's songs are easy enough to get into, with chord changes, arrangements and harmonies that are both familiar and unexpected. His vocal delivery is soft, sometimes breathy and conspiratorial-sounding, as if he's sidling up to us to let us in on something that the squares shouldn't be hip to. Zarookian's musical mechanics would be acceptable in both the churches of Wilson and McCartney. It's simple, but not simplistic - in the realm of music composition, Spirit Kid is more a I-IV-II-V situation than a simple I-IV-V. It's that extra, exquisitely tasty twist that has sustained the project through the five years until its official unveiling in January of 2010, Spirit Kid's "birthday."

"The plan for a while was to release this under my own name and call the album "Spirit Kid," but more and more I realized that I preferred to have a pseudonym," explains the singularly-named and easily Googleable Emeen Zarookian, finding comfort in the "suit" that the stage name provides. Uncomfortable with both the glory-finding spotlight and the flaw-finding magnifying glass, Spirit Kid was born. It's also presumably easier to fit on a marquee than "The Emeen Zarookian" band and besides, "There is a stigma that goes with the first-name/last-name thing," he explains.

While he sings and writes songs, Zarookian doesn't see himself the classic version of the singer-songwriter, traveling with naught but an acoustic guitar and a milk crate to sit upon. "I've tried that and I think it's boring," he says. "How could anyone watch it and not think it's boring?"

The decision to make Spirit Kid into a fully functioning band did not come as a mere alternative to playing coffee houses. Zarookian realizes and materializes his songs as he hears them, which sometimes includes a few extra bodies and instruments. "I'll say, 'This part has this crazy drum fill and it leads into this big reverb blast and then it all cuts out and there is the double-tracked vocal and guitar.'" He pauses for breath, clearly not for lack of ideas, before continuing with the arrangement, "'Then bass comes in and then it all comes together for the chorus and...' You just can't do that with an acoustic guitar."

While he usually records all of the instruments for his projects, as he did on his initial Spirit Kid release, Zarookian has now also recorded with core band members Andrew Sadoway (drums) and Matt Sisto (bass), both close friends with their own long-running musical rap sheets.

Along with Zarookian's sonic abilities comes the talent of packaging feelings that are both very intense and very real into an almost whimsically melodic sound, full of quarter-note piano chords, walking bass lines and background vocals that pop out of the ground like mushrooms in Pepperland. He sings of heartbreak and other strife-filled moments over "You Won't See Me"-style oooh-la-la-la background vocals that coat the whole experience in irresistible musical sweetness.

"A lot of the material is very personal to me and getting it out is already hard enough," confides Zarookian, who has unwittingly created a situation where the audience cannot get enough of his own personal strife and observations. And that's all OK to him.

After the record-release show, or birthday show, Zarookian said he was impressed by how easily the set came together and tried to deflect credit away to his friends, bandmates and others. But the real reason for success is the music of Spirit Kid, which has been almost a lifetime in the making. The birthday present is unwrapped and it's no doubt the first of many. Spirit Kid is dialed into something both intricate and simple, enjoying the hearty shredded wheat as well as the frosted outside - and letting everyone else in on the fun.

"Have I been waiting and anticipating this moment my entire life? No. I've been making music with all sorts of people, learning and sharing, always wanting to grow," explains Zarookian.