Ironic in name only, the Kirkwood Ballers Club is quickly becoming a vital outlet for Atlanta's improvised and otherwise adventurous musical communities. Since March, the weekly congregation of jazz, noise, punk and occasional hip-hop artists has been steadily building steam with its free Monday night improv sessions at Lenny's. And word is spreading.

The KBC started as an irregular gathering of artistically balling players, organized by Nisa Asokan and Randy Castello in Asokan's Kirkwood home of the last six years.

"Initially, we had close friends come over to the house and just rock it," says Castello. "Get a keg, hang out and play music. It was all improv-based and all over the place -- beats, MCs and jam sessions."

After Castello's own freeform Americana act, the Flakes, played an open-mic night at the Brandyhouse in Buckhead, he decided to initiate his own grittier improv night closer to home. Asokan, Castello and his fellow Flakes -- drummer Alex Lambert (Blame Game, Lie and Swell) and guitarist Patrick Foley -- along with James "Mr. Mips" Parker and Bradford "Deer Hunter" Cox began moderating the weekly event.

Everyone from noise provocateurs Wilson+Heath to jazz percussionist Kinah Boto (the artist formerly known as Woody Williams) have made appearances. The number of spectators for the event has noticeably increased, prompted by no means other than e-mail notice and word-of-mouth.

"You never know what to expect," says Castello. "Just when you think it's going to be a stale night, there's one performance that makes it a memorable night."

The Kirkwod Ballers Club takes place at Lenny's every Monday at 9 p.m. Free.