By Kimberly Chun

OUTSIDE THE THREE -month-old reggae music store Wisdom Records on a recent winter morning, the scene is pure Silver Avenue. Bundled-up, working-class Excelsior residents brave the rain and cluster like satellites around the bus stop next to signage-happy Joe's Cable Car Restaurant ("Joe Grinds His Own Fresh Chuck Daily"). Meanwhile, a flight above Joe's, in a former real estate office, "Hot Girl" is piggybacking "Joe Frasier 2004" while "Hormone," "Stress," and "Freedom" vie for attention.

Those are just a few of the new rhythms wearing out needles and burning up the dance halls in Jamaica, and Wisdom co-owner Javier Ibarra is just the reggae obsessive to help you navigate those hothouse beats. Buzzing a visitor upstairs, Ibarra – known as DJ I-vier when he's teaming with Spliff Skankin' for KPFA-FM's Reggae Express or spinning at San Francisco's Club Six, Oakland's Oasis, and Berkeley's Shattuck Downlow – stands behind the counter next to a set of turntables, ready with a smile and the discographic knowledge necessary to scope out his goods.

What Wisdom might lack in so-called island atmospherics it makes up for in other traditional ways – mainly Ibarra's rangy selection of 7-inches by the latest and greatest (read: oldie) artists and producers. The merchandise reflects the anarchy of a subgenre-filled Jamaican music scene that continues to cherish a musical delivery system, the 45 rpm vinyl single, that's all but an anachronism in the States.

Though the shop carries its share of conscious urban garb and books (overseen by Ibarra's girlfriend, co-owner Alexis Friedman) as well as DVDs, vinyl albums, CDs, and mix CDs, the singles are the stars here, unlike at older reggae stores such as Reggae Runnins Village Store and EIW Reggae, which focus on lifestyle merchandise and clothing. At one set of turntables overlooking the stairs, customers can try out discs on their own. But what also distinguishes Wisdom from other shops is its 24-year-old owner's personal touch, modeled on the style of Jamaican record shops. Ibarra keeps all the newest singles behind the counter, and on a nearby dry-erase board he charts the newest sizzling rhythms from Jamaica, which this wintry week include Wireless, on the Digital 1 label; Heavenless, on Pown Daddy; and Black Survivors, on Weeded.

The number of singles that use each rhythm is neatly marked on the board, but you have to ask Ibarra for the singles themselves. (Multiple 7-inches with the same rhythm are created by producers who offer their rhythm to various artists, thereby flooding the market with the beat – a way, some say, of foiling that pre-download, old-school form of "pirate": the copycat.)

At some stores the search can be frustrating for a DJ looking to blend a set of songs with the same rhythm. Ibarra makes it easy. "We can sell you the whole rhythm, whereas some places you have to individually find each artist," he explains, playing Spragga Benz's take on the Fear Factor rhythm. The latter, also featured on the latest Elephant Man song, "Anaconda," can't be heard on that dancehall lothario's current full-length, Good 2 Go (Atlantic/VP).

Specialization, customer service, and unique merchandise are the way to go for a small music retailer, says Gabe Lautaro (a.k.a. DJ Riddm), the owner of Funky Riddms Records, a shop specializing in vinyl hip-hop and funk as well as reggae. "Record stores are becoming a thing of the past as more and more people download music, so if you don't have something to offer as far as services or knowledge, you don't offer a lot," he says.

Staying current will be the trick for Ibarra, who has never owned a music store before but got hooked selling records to other DJs out of his nearby Mission District living room a few years ago. Now the S.F. native relies on distributors in Jamaica, New York, and California. "Literally, I'd say, something like 50 new records come out every week," he says.

Thus far Ibarra's primarily DJ clientele isn't large, but fortunately his customers tend to buy plenty of records at a time. And in the style of reggae DJ-producer-record merchants like Coxsone Dodd and Prince Buster, Ibarra eventually wants to expand Wisdom to encompass a studio and then a label, with help from his DJ crew, Jah Warrior Shelter Hi-Fi. "I think it's underestimated," he says, "how much potential there is for reggae in the Bay Area."

Wisdom Records 4308 Mission, S.F. (415) 841-1258, www.wisdomrecordssf.com.

Reggae Runnins Village Store 505 Divisadero, S.F. (415) 922-2442.

EIW Reggae 4438 Third St., S.F. (415) 648-3125.