Cruise lines are trying to diversify themselves. The following four companies aren't by any means cornering the market, but in one aspect or another they represent a departure from the traditional method of voyaging.

Carnival is zealously going after the mass audience, while Sea Goddess is limiting itself to the select few. Windstar is harking back to the days of sail, while Exploration seeks out destination-minded passengers. Carnival Cruise Lines. "Some cruise lines are afraid to put a personality on their ship," says Bob Dickinson, senior vice president for sales and marketing at Carnival Cruise Lines. "They want a vague image of posh, upper-class, sedate ships that appeal to children, families, the middle-class, younger people -- but you end up with an amorphous cruise experience."

Passengers on Carnival -- which bills itself as "the fun ships" -- don't have a problem with vagueness. The line, which charges a basic price of $180 per person per day, draws its passengers from the same broad segment of the population as such other large cruises lines as Norwegian Caribbean, Royal Caribbean, Princess, Sitmar and Holland America.

"We're after the Everyman. We're a microcosm of the traveling public, geographically as well as age- and income-wise," says Dickinson. "Only people who are dismayed if someone is on board who isn't from the Social Register shouldn't be on Carnival."

The Miami-based Carnival operates five ships, carrying from 1,000 to 1,650 passengers each. The vessels sail out of Miami, Fort Lauderdale, Fla., and Los Angeles on three-, four- and seven-day trips to the Bahamas, Caribbean and Mexican Riviera. The ports of call are relatively unimportant, says Dickinson: "To us, the ship itself is the destination."

*Sea Goddess Cruises Limited. Royal Viking and Cunard lines, along with the Norwegian Caribbean's Norway, all offer traditional luxury cruises, but it is a new company, Sea Goddess, that perhaps takes the idea to its limit.

Based in Miami, Sea Goddess' two ships carry a maximum of 116 passengers each. Both ships spend the summer in the Mediterranean; in the winter, one goes to the Caribbean, the other South America. Ports visited include such offbeat destinations as Saint Tropez in France, Puerto Banus in Spain and the Tobago Cays in the Caribbean.

"On most cruise ships, if you wanted a steak at 3 in the morning or 3 in the afternoon, you'd have a difficult time. If you wanted to sleep beyond 9 in the morning, you'd find that difficult, too," says Sea Goddess president Ron Kurtz. "But we try to provide a lack of regimentation. Sea Goddess is like a house party."

The on-board casino and piano bar, the discouragement of tipping, the private bar in each of the suite-like staterooms, the cooking of all food to order and the relentless luxury has a cost, of course: The price of a Sea Goddess cruise is $600 per person per day, three times the industry average.

"We have a high-priced product, but we offer value to the people who can afford it," says Kurtz.

*Windstar Sail Cruises. Windstar is trying to take a step forward by taking a step back, to the days of sail. The Miami company's first ship, the 150-passenger Wind Star, has 21,700 square feet of computer-controlled sails on four masts. Capable of being powered by either the sails or a diesel engine, the ship looks in artists' renderings like an elegant cross between a sleek yacht and a 19th-century clipper ship.

The Wind Star's maiden voyage is slated for Dec. 14, 1986; a sister vessel, the Wind Song, will be launched the following spring. The first ship will sail the Caribbean; the schedule of the second ship is undecided.

"We try to offer the feel of a yacht and the comfort of a cruise ship -- good food, big cabins," says William Kyle, a consultant working with the line. The cruise price is $225 to $300 per person per day, depending on season.

As with Sea Goddess, there will be an emphasis on luxury and a lack of regimentation, but Windstar is aiming more at the sports-minded. The ships will carry surfboards, diving gear, deep-sea fishing equipment, small sailboats and wind surfers.

*Exploration Cruise Lines. On many traditional cruises, the voyage is the thing, with the ports of call -- if any -- an incidental diversion. Seattle's Exploration Cruise Lines takes the opposite approach, using small ships that are specially designed for access to remote and unusual places. On Exploration ships, there's a heavy emphasis on the areas visited, and all shore explorations are included in the price -- not the usual condition on most cruise ships.

"Our clients are more participatory and adventuresome than on the average cruise ship," says Exploration president Robert Giersdorf. "They're more apt to be the ones who will go ashore and get intensively involved in the natural and cultural history of an area."

Exploration operates six vessels, each carrying from 80 to 160 passengers. The ships sail out of Seattle; Ketchikan, Alaska; Prince Rupert, British Columbia; Boston; and, for one-week spring and fall cruises on the Chesapeake Bay, Washington. Other destinations include Tahiti, Panama, Mexico, Costa Rica and numerous ports in the Caribbean. Price per person per day ranges from $175 to $285.

For those seeking adventure amid greater luxury, the company this year is launching the 250-passenger Explorer Starship, which will sail among the smaller Caribbean islands. Prices will range from $300 to $350 per person per day.