The old Quinby Building downtown stood empty for years, a relic from the Jazz Age destined for a date with the wrecking ball.

"It was a real dog," says Gene Elmore, the building's new owner. But today a visitor to the Quinby enters a lobby restored to its 1926 elegance, with polished brass and marble that shines gray and purple. A courtly elevator operator welcomes you aboard. Which floor? World Access? MCI? Level 3 Communications?

The Quinby Building has "gone telecom," and so has been reborn. There's just one hitch. There aren't any people. Just machines.

The Quinby is now a giant hive of fiber optics, cabling, power lines and computers. It is, in fact, one big switching station tended by a handful of technicians who work for Internet service providers, e-commerce outlets, and local, national and international telecommunication companies. The old Quinby has been wired and now can handle 14 million calls simultaneously. That is some major bandwidth.

As the Quinby went telecom, so too have another dozen old office buildings and shuttered department stores in downtown Los Angeles, and today there are "For Lease" signs on another dozen, announcing "Telecom Space Available" or more simply, "Bandwidth Available."

A study by Howard Sadowsky of the real estate firm Julien J. Studley in Los Angeles found that more than 1 million square feet of downtown L.A. office space has gone telecom, some 150 companies taking about 6 percent of the available space.

"It's like everything else," Sadowsky said. "If it's a couple of buildings, you might not even notice. But if we convert everything, it's a ghost town."

While the telecom real estate boom is good for a landlord like Gene Elmore, who gets double and sometimes triple the average office rents, the growing presence of buildings filled with machines and not workers is giving boosters of downtowns around the nation pause because, the formula goes, you need people to revitalize the core cities: workers in offices, residents in apartment houses.

For years, civic boosters and the political class in Los Angeles have made stabs at revitalizing a once-vibrant downtown, particularly its derelict edges of flop houses, abandoned warehouses and soulless parking lots. While downtown Los Angeles has its towers of gleaming glass, its former boulevards of power and commerce, as well as its once glorious movie palaces, are today a fraying skid row. Vacancies are running as high as 20 percent, and many of the older buildings and department stores are empty except for their first floors.

Recently, downtown L.A. got a new sports and entertainment arena, the Staples Center; a new cathedral for the largest Catholic diocese in the country and a Walt Disney Concert Hall are in the works. One group of developers has even proposed erecting a monument of a 1,000-foot sword-wielding angel on a downtown hillside.

But there has been a lot of renewed grumbling in the last two weeks about how there's "no there there" in Los Angeles. The latest round of civic introspection came about after Los Angeles's New Year's Eve celebration, which many here criticized as paltry after the great civic parties held in New York, Washington and Paris. Here, Y2K was toasted by lighting up the Hollywood sign, but not actually going to the sign. It was off-limits. And so the desire for a more public space--a Times Square, a National Mall, an Eiffel Tower--continues.

Downtown enthusiasts are still hoping to turn the city core around and entice people to live downtown, and some of them fear that the telecom spaces could derail their dreams.

"We view the telecom phenomenon as a mixed blessing at best," said Ken Bernstein, director of preservation issues at the LA Conservancy, which seeks to protect historic buildings. "On the one hand, the telecom business is saving some beautiful old buildings that were threatened with demolition. On the other, if enough buildings go telecom, you could begin to suck the life out of downtown."

The heavy demand for telecom space is not limited to Los Angeles. "We got telecom buildings we're looking at in Milan, Miami, Jersey City and Madrid," Elmore says. "I can understand why there are some real concerns about replacing people with machines in a downtown. This isn't just a phenomenon in L.A., but everywhere."

But Elmore says that economics, not social policy, is driving the trend. With the explosive growth of the Internet and the deregulation of the telephone industry, there is suddenly a great need by many communications companies to be located as close as possible to the main switching stations, such as those operated downtown by Pacific Bell and AT&T. Every city has such a hub, a sort of modern crossroads of wires and fiber optics. The idea for telecom companies is to locate as close to these hubs as possible and then jack in.

The older buildings around Pacific Bell and AT&T central switching stations are prime candidates for telecom conversions not only because of their physical proximity, but also because of the very nature of old buildings. They have to be retrofitted anyway to meet modern codes, and so during the conversions they can be stuffed with new cabling. Also, the older buildings often have higher ceilings and their floors can support more weight, both attributes sought by the telecom companies for their equipment.

Telecom buildings are usually filled with far fewer employees. Elmore estimates that telecom companies typically have about one employee for every 2,000 feet of space, compared with one worker for every 150 square feet in a standard office.

Moreover, the telecom companies tend to fill up an entire building, not just a few floors. And they like it this way: Telecom companies do not like a lot of foot traffic because they are very mindful of security. They don't want anyone coming in and pulling a lot of switches.

Los Angeles Mayor Richard Riordan and his staff worked to steer one large telecom operator, Level 3 Communications, away from the historic Terminal Annex postal facility downtown. Rocky Delgadillo, the deputy mayor and head of economic development efforts by the city, says the telecom building phenomenon is, overall, good for the city. It just needs to be managed. But managing growth has not exactly been of one of L.A.'s strong points.

--William Booth

CAPTION: Gene Elmore inspects cables in the Quinby Building, which he restored. The former office building is now stuffed with telecommunications equipment.

CAPTION: Outside, the Quinby Building can be deceiving. While millions of calls transit it, there are no office workers behind the windows to answer the telephone.