Aaron Smith’s career path, as he tells it, was carved out by the time he was 7 years old.

“When I was 7, that was it,” he said, remembering how his parents handed him a plastic guitar that basically changed his life. “It was magical. I knew that’s what I was supposed to do.”

The guitar, simple though it was, had the advantage of being electric, and that meant it generated the sort of loud noise — or music — that could please a little kid.

But something deeper had seized Smith’s imagination when he started playing that guitar, and he kept at it. In another year or so, he said, his parents bought him a black acoustic Harmony guitar, “once they figured out I was going to take it seriously.”

And he has.

Smith, 31, manages Meridian Underground Music, helping area musicians perform in all sorts of ways.

He works on wiring, microphone levels, instrument tuning and other tasks for musicians who play during Saturday-night performances and for open-mic nights on Thursdays.

The Thursday and Saturday events are free, he said, with enough bands willing to play in Meridian for the exposure they receive to keep those nights alive. Open mic nights start at 6 p.m. on Thursdays and can run to about 9 p.m. Live shows, usually scheduled on at least one Saturday per month, also start at 6 p.m. and run until 10 p.m.

Smith also crafts custom-made guitars, and he plays a range of guitar music on his own.

Smith, who’s worked at MUM for two years, said he records the open-mic night performances and MUM owner Wayne Williams takes video. Smith said Williams’ son Dyson does the editing and Jonathan Parkison mixes the sound. Smith mentioned Chad Fuller, Days of Broken Fate and Batty Pat as among the artists who play frequently at the establishment.

If Smith’s musical lightning bolt struck when he was seven, in the shape of a plastic guitar, the fire that followed burned with a steadier flame.

“I got my first actual nice guitar, a Gibson Les Paul, eight years after I started playing,” he said. “I was 15.”

In his early years of playing, Smith, who grew up in Lauderdale County, absorbed much of his musical learning through church.

“I learned to play chords in church from my youth pastor, and it was just by ear after that,” he said.

He also drew strong influences from his mother’s side of the family, the Valentines.

“They were all heavy into Bluegrass,” he said, but noted that they supported the rock-ish turn his own music took. Smith remembers his uncle, David Valentine, telling him that his hands were made to play the guitar. He also recalls the way his mother helped to give his music an edge.

“She was my main rocker influence,” he said. “She listened to Queen, to Bad Company, to Lynyrd Skynyrd, to The Doors. Even on our way to church, she’d have the music going. That’s kind of like a mixture there. I’m going into church, but I’m rocking out on the way.”

As Smith grew up, he listened especially closely to Zakk Wylde, Ozzy Osbourne’s guitarist, and Eddie Van Halen, who collaborated with Meridian’s Peavey Electronics to create the Peavey EVH Wolfgang guitar series. Smith also mentioned guitarist Steve Watson, a mainstay of the local music scene, as a big inspiration.

Now, Smith works with younger musicians, including Jaywaun Johnson, a Meridian Community College student who frequently comes out to Thursday’s open-mic night to play his guitar.

“I cover from classical all the way to the classic rock of the ‘80s,” said Johnson, who studied at the Detroit Institute of Music Education. “And everything in between.”

Johnson said the atmosphere on Thursday is relaxed.

“No one’s going to boo you off the stage,” he said. “Everyone’s just encouraging — they want you to get up and perform if you want to.”

Johnson also helps set up audio and camera, and he gives assistance to “the occasional roadie,” he said.

“Everything I do, he’s right there with me, left and right,” Smith said of Johnson.

As for Smith, he also works on guitars at Meridian Underground Music, spending some of the time creating custom-made instruments. On a recent afternoon, he was working on a sleek-looking black-and-gray guitar.

“With this one,” he said, “it’s going to be more like an Iron Maiden rock-style guitar. Sort of an ’80s, good rock guitar.”

He talked about positioning the strings.

“You set the action,” he said, referring to the distance of the strings from the frets.

“If it’s got high action, it’s tough to push the strings down,” he said. “If it’s got low action, you can just barely touch the note to make it play.”

He said heavy strummers want higher action, more distance between the strings and frets, than lead players, who might do fast fingering and want quick reaction time.

As Smith worked, customers came by, asking about the types of guitars the store carried and the sort of work he was doing on the custom piece. Smith said these are the customers who might show up for the open-mic night on Thursday.

“Folk, blues and country are some of the main things people play here,” he said, noting that as many as 30 people might come out on a Thursday night.

“Typically the open-mic people come and hang out and watch each other and record and take turns,”

And as Jaywaun Johnson noted, there’s no pressure to perform on Thursdays — other than what might emerge from a person’s own deep-dwelling musical impulses.