At 30, psychologist Robert Cole did something that had friends suggesting he was in need of treatment himself: He ditched his mental-health career to open a stereo store in what was then largely rural Montgomery Township.

It was 1979. World Wide Stereo had made its debut on Route 309 less than a mile away from the new Montgomery Mall.

Only months earlier, Lee Swede had opened Wall to Wall Sound in that mall with the goal of dominating the growing area's audio market.

As Cole remembers it, Swede, executive vice president of the Wall to Wall chain, paid him a visit with this welcome-to-the-neighborhood greeting: "I . . . just want you to know I'm putting you out of business in three months."

Thirty years later, Swede is retired and living in Margate and Florida, not remembering those words to Cole, but not denying his competitive spirit.

And it is Cole's store - now called Bob & Ron's World Wide Stereo - that has prevailed, having outlived Wall to Wall, which went bankrupt in 1990, and at least a dozen other competitors.

Its staying power is about to be tested yet again - in a real in-your-face way.

From the front door of his showroom of high-end equipment, Cole has a stomach-churning view of crews finishing a $2 million retrofit of a largely vacant big-box property slated to become the first Sixth Avenue Electronics store in Pennsylvania.

It will be store No. 15 in the 29-year-old Sixth Avenue enterprise, a family-owned business based in North Jersey's Springfield, Union County, that reports $400 million in annual sales.

Cole said his two stores (a second opened in Ardmore in 2000) had combined sales of $14 million last year.

During a visit to Montgomeryville last week, Sixth Avenue chairman Billy Temiz said he expected - despite a substantial amount of exposed wiring and unassembled display shelves - that the 25,000-square-foot store would be ready for customers by May 11.

Asked why the exterior lacked signs that even hinted of Sixth Avenue's impending arrival, Temiz coyly replied: "We don't like our competition to be jealous."

During an interview earlier that day, Cole ran through a range of reactions about the prospects of facing a fresh competitor. Jealousy was not among them.

He was complimentary: "They're a very well-funded company, and they build a beautiful store."

Confident: "We've built a core business that nobody has been able to knock off."

Realistic: "I'm not stupid. They have a lot of money."

Gritty: "However they do whatever they do, we're going to do it better."

Temiz, 56, is a Christian Armenian who moved to this country in 1977 from predominantly Muslim Turkey to enjoy freedoms, business and otherwise, that he did not have there. He opened the first Sixth Avenue store in Manhattan in 1980 at 38th Street - and Sixth Avenue, naturally.

His brother Mike is president of the company, which, like World Wide Stereo, prides itself on long employee relationships. (Both companies offer health and 401(k) plans, among other perks.) The typical Sixth Avenue employee has 12 years with the company, said Tom Galanis, vice president of operations.

Cole included "Ron" in his business' name to acknowledge one of the first employees he hired, who is still with him. He summed up his workforce of nearly 60 - spread over two stores and a technical support and administrative site in Hatfield - this way: "Eighteen percent of our staff is here over half their lives."

For its Montgomeryville store, Sixth Avenue has hired locally. A number of those 40 employees recently lost jobs when Circuit City and Tweeter went under.

Billy Temiz said he meant no antagonism in selecting for his premiere Pennsylvania store a site across the street from Cole's. The company's policy is to own all its retail locations. When the building on 309, near the Five Points intersection, became available - offering the kind of space Sixth Avenue wanted for its myriad showrooms and custom-design areas - Galanis said the company couldn't pass it up, especially with the area's demographics so "very, very good."

They have spent much renovating the property - the floor is covered in granite tiles in shades of cream and black - in a nod to European-style retailing.

"European stores are extremely luxurious," Galanis said, noting that that also applied to their sales people. For that reason, visitors to the Montgomeryville Sixth Avenue store will find all employees in at least shirts and ties, with most wearing full suits, he said.

They'll also find display cases of iPods, cameras, camcorders, and cell phones - all things that World Wide Stereo does not carry.

That difference is part of the reason Galanis insisted World Wide Stereo had little to worry about when it comes to Sixth Avenue's presence in eastern Montgomery County.

"We feel we'll probably take business from Best Buy," he said.

Best Buy, the consumer-electronics industry leader, has a store in Montgomeryville, too, across from the mall. A manager there said any comment had to come from corporate headquarters. A corporate spokeswoman declined to comment.

At the Progressive Retailers Organization, a Chicago buying group of independent electronics retailers, executive director David Workman wasn't about to take sides in the imminent showdown in Montgomeryville, even though Sixth Avenue is among the cooperative's 19 members.

With annual sales of about $9 billion, Circuit City's demise "has freed up a tremendous amount of business in literally every market," Workman said.

Describing World Wide Stereo and Sixth Avenue as "very, very good operators," Workman predicted that each company would do well in Montgomeryville - even in the throes of a recession.

They're off to an amiable start. Cole and Galanis attended a meeting in Cozumel, Mexico, in February for top dealers of a certain line of electronics. They dined together several times, they said, and liked each other.

Contact staff writer Diane Mastrull at 215-854-2466 or dmastrull@phillynews.com.