By Bobby Feingold

On a cold Friday in a damp cave, a scraggly-bearded character in a technicolor blazer shouted from his soul.

“Sometimes I feel like a motherless child,” he said as the crowd looked on. The group backing the colorful leader began to stomp along to music projected from a small amplifier.

Then, the audience started clapping like they were listening to gospel music in a church. Initially, it backfired, but it picked up again, a testament to the faithful crowd believing in the cause.

Lighters went up.

The audience had the spirit.

As the E-line train approached the Symphony stop around 10 p.m. Friday night, passengers onboard looked captivatingly at the performance in front of them. Intrigued by anything different from their normal subway routine, their faces showed surprise at the group of musicians and the growing crowd of about 50 students and onlookers, all moved by the same idea of expressive freedom.

They were in the presence of something like Northeastern’s own musical messiah.

Elias Bouquillon, a middler music and philosophy major, set up the concert, which served as a meeting of the Symphony Underground Collective (SUGr).

The concerts are held every Friday at 9:30 p.m. Bouquillon created the idea last fall in honor of his grandfather, Donald Armington. He loved “tinkering with audio,” he said.

Throughout the night, Bouquillon’s message was clear: “expression is sweet” and “music should be free.”

“None of it has been planned,” he said. “I allowed it to grow. It started as a seed that I planted – I don’t feel like I planted it!”

Though he had never played a show in Boston after five years of trying to record his music, he said it all came together in the last couple weeks before the first concert. After the initial performance, one of the fellow musicians and good friends urged him to do it every week.

It snowballed from there.

The desolate T-stop and rotting, white stucco walls served as a bland backdrop for Bouquillon’s vibrant idea. Brightly lit, the buzzing of fluorescent lights and rumbling of trains allowed for light conversation and much music. Bouquillon said he enjoyed the cave-like setting because of the natural feedback loops and echoes it added to the music.

In fact, the music forces him to adapt to the setting.

Symphony Underground is primarily a circle of up to six musicians. Each week a different number shows up, so it has turned into a rotating lineup. As Emily Kimball, a sophomore music technology major and fellow musician, put it, “It’s a nonformal group but a formal performance.”

Kimball, who usually plays folk in the vein of Ani DiFranco, took a break from her usual style to join the collective on Friday.

Another of the players, freshman computer science major Peter Anderson, said he joined the group for a chance to play.

“I wanted to jam with people,” Anderson, who plays bass and trumpet, said. “It’s an opportunity to perform.”

With a cow-patterned guitar strap holding his guitar around him, Bouquillon was constantly scurrying in the background, making sure everything was in place.

The musicians were eager to see him arrive.

They set up in front of the MBTA public safety board, with the faces of T officials smiling down on them.

It was if they were Bouquillon’s own personal angels granting favor and approval on his creation.

Every week’s concert has a different theme. That night’s performance was titled “Leave the rest for the rest of them.” It was SUGr’s seventh week.

Songs included Velvet Underground covers, what Bouquillon called “earthy, crunchy” acapella songs like “Home on the Range” and some of the members’ original songs.

“It’s liberating, playing songs I wouldn’t normally play,” Kimball said. “People wanted something like this to happen, and Eli makes it happen. He’s rare. He’s devoted to his cause.”

And that’s exactly what it is to Bouquillon.

He is adamantly against rich musicians. Other music, he said, is much more honest. He said he wants to “pull the carpet beneath the music industry.”

He plans to write a book about the experience.

And, thanks to his creation, his show can always remain portable.

Bouquillon said he developed the Suitcase Studio to provide all musicians, especially those without the financial resources, the means to record their music at any time, and in any place. His prototype is used during each SUGr show to record the music from that night and publish it on the Web. It is completely self-contained in a cello case.

He plans on developing and patenting it as his co-op, describing the undertaking as his “hope and dream.”

As the night got colder, the crowd got bigger. Different viewers of various ages gathered. As the train approached, blowing everyone’s hair, a nervous tension arose.

After the show, the group filed in to his crowded apartment bedroom to unwind.

Bouquillon immediately plopped on his futon with his legs folded over each other.

His room was filled with a piano, drawings on the wall, and other assorted instruments. Sitting down for an interview, he immediately began talking before a single question was even asked.

“I built the fire, now it’s just burning,” he said. “I’m making it as easy as possible for everyone to throw a log in. I believe this fire is good.

“I don’t worry about the logistics getting to expressions. I build on and practice what sounds good,” he said. “The best learning is from myself. I’m flooded with what I’m doing right and wrong. There’s no time for an ego to be emotionally attached for mistakes.”

Brandon Totten, a freshman sociology major, said it was his second time attending one of the concerts.

“I enjoy local music,” he said. “It’s fun and amusing and free.”

As for passersby, Totten suggested that some people may not understand the show. “People give the weirdest looks,” he said.

People want SUGr to work. After one error, the group nervously laughed it off and continued playing. When one of the musicians dropped his guitar pick three times, there was someone who immediately grabbed it and returned it to him every time.

“Details are important. It’s like the nails of Noah’s Ark,” Bouquillon said. “I can’t mess up on a nail because then the whole ship will sink.”

Raised Roman Catholic, Bouquillon uses a lot of religious terminology.

“It’s that intense to me,” he said. “I need to use that kind of language.”

His low voice and soft features made his ideology welcoming. With his chipmunk smile, he explained how it’s what is? all philosophical. “It started off simple but turned complicated.”

Midway through the show, Bouquillon set up a tip jar surrounded by scarves. They only made $1 that night, but the crowd went into applause when it was received, proving that collegiate musical messiahs need to eat.