On Thursday, when the clock strikes twelve in downtown LA, men and women in suits pour out of office buildings looking for a place to eat during their one-hour lunch break. But for some, an appetite for music quells their hunger, and they head over to the First Congregational Church of Los Angeles, a gothic-style cathedral sitting anachronistically on Commonwealth Ave.

One step into the cavernous sanctuary and the bright sunlight and sounds of the city fade, replaced by dim chandeliers and silence. Soft light spills through the various stained glass windows and a delicate trace of incense hangs in the air. Business people, families, men with dreadlocks, and elderly couples--all speaking in murmurs--fill the pews. A sense of the sacred envelops them.

At 12:10, a deep note reverberates through the church, striking the deepest part of one's soul. First Congregational Church of LA houses the largest church organ in the world, with 20,000 pipes surrounding the interior of the building. Organist-in-residence Stewart W. Foster sits at the organ, which is at the front of the church. Rows of keys, knobs, and pedals allow him to open the numerous pipes. The result is an orchestra of sounds: the deep bassoon-like bass, the lively piano-like midsection, the woodwinds, and the light whimsical chimes. Melodies compound upon melodies as Foster's fingers and feet race across the instrument, controlling every note.

Bach's Passacaglia in C minor starts with music clearly emanating from the front of the church. The music crescendos while growing in complexity until suddenly deep loud notes emerge from the largest pipes located in the back. Listeners turn around to peek at the towering organ pipes, the sound swelling to fill the space, the wooden pews vibrating with each note. The piece ends with applause, and Foster takes a little break before beginning Bach's "Allein Gott in der Höh' sei Ehr," which is translated to "All Glory Be to God on High." Its harpsichord sound, with etherial tones reminiscent of wind chimes, marks a sharp contrast with the previous piece.

Foster grew up around organ music. His mother played the organ at church. He started playing the instrument at the age of six, before his feet could even reach the pedals. He is grateful for his early start: "I grew up physically adapting to it - organ playing requires a lot of coordination because you are using two feet and two hands. I was able to develop muscle memory and motor skills at a young age."

He studied piano and organ solo performance at Interlochen Arts Academy, and then went on to major in organ in college before traveling to Paris to study under organ master Suzanne Chaisemartin. Since then he has won numerous awards and performed recitals on some of the world's most prestigious pipe organs. Still, Foster says playing this organ is like nothing else: "It's like sitting at the cockpit of a 747, there's so many pipes, so many possibilities."

Before Foster even starts playing, it takes an hour to set the stops to the sounds he wants. The size of the organ magnifies the sound: "It's a symphony times five. Instead of 9 oboes, you have 45...It's a lot of fun."

Foster has been the organist-in-residence at the church for six years, playing during Sunday worship, weekend weddings, and these free weekly midday concerts. He loves the organ's setting: "It's not only about the size of the organ, but the beautiful space it's in. It creates an experience that is very spiritual with the church's stain glass windows and gothic high-vaulted arches."

He ends the concert with a famous organ piece, Bach's Toccata and Fugue in D minor, which is often used in media to set a haunted mood. The deep sounds tower over the audience, evoking thoughts of the Phantom of the Opera, before giving way to a run of high notes chasing after each other. The notes head back to the deeper range and the back pipes are resounding again. The last note reverberates in the air as the audience applauds and Foster steps off the stage. It is 1 p.m. --- just in time to head back to work.