Madonna's already done it; Sting's about to join her. Coming soon: Paula Abdul and Janet Jackson.

Is it Broadway? A movie? World tour?It's QSound, a new recording technology that turns an ordinary set of stereo speakers into a kind of 3-D sound system, according to its developers. Madonna just released the first album using the system, while the rest are working with it now.

"You'll hear things in the songs you've never heard before," promises Shep Pettibone, who mixed Madonna's "Immaculate Collection" greatest hits package. "The whole idea is to make stereo more stereo, to sound even better."

Basically, the system enhances the stereo effect that makes sounds appear to be projected from their source instead of coming from the speaker. A computer with a special software program is attached to regular production equipment during mixing to create the effect.

There are just six of the QSound recording systems in the world: one in New York, one in Europe, two in Los Angeles and two in Canada. Pettibone - with frequent visits from Madonna - worked at the one in Manhattan.

The result: congas popping in from your right ear, synths from your left ear, Madonna's vocals coming in and out from either side - all of it several feet from your speakers.

"Finally, something that compares with the little sounds in my head," said Madonna after hearing the results.

It's a long way from the first demo developed to promote the project: thunder claps and a growling bear that "sounded like a sick moose," said Lawrence Ryckman, president and chief executive officer of Archer Communications Inc., which is a partner with QSound's inventors.

"It was quite embarrassing, but it worked," Ryckman said of those early days.

Rocker Julian Lennon, who's planning a QSound recording, recalled his first exposure to the technology as less than inspirational: "I heard it about a year ago when - to put it politely - it wasn't very good. . . . It's gotten better with time."

QSound was conceived in 1980 by co-inventors Dan Lowe and John Lees. The project was put off by financial difficulties for several years until Lowe met with Ryckman in late 1985.

Ryckman was convinced Lowe had something; after several years of raising money and industry interest, they finally brought QSound to the fore in the past 18 months. In addition to music, QSound will be used in the 1991 generation of Nintendo games, Ryckman said.

The process could add to the cost of a tape or CD, because, Ryckman said, QSound will get a royalty on each record sold just as singers and bands do, adding to record companies' costs.

Lennon became a QSound convert after hearing a demo of the new Sting album, "The Soul Cages." He is now writing his next album in anticipation of using the system for the whole thing.

"The mix I heard for Sting's new album blew me away totally," he said. "After that, I said, `This is for me.' It's an extra dimension. I always believed there was more out there, and we've found something."

Singer Freddie Jackson giggled giddily when he took a break from using QSound to mix his new single, "Do Me Again."

"I heard the system, heard the quality, and I was floored by it," he said. "I want the music to sound like it's live on stage. That's the exciting thing - it's like live. I think everyone is going to be floored by the sound."

Hugh Padgham, who produced the new Sting album, was more over the top: "QSound will do to stereo what stereo did for mono."

So does this mean QSound is the wave of the future? Those who've used it say for certain things, yes; for other things, no.

"The main concern I have is it loses the drive of the song," said Goh Gotoda, the engineer on Jackson's single. "For certain things, it's very nice - Freddy's vocals, for example, it gives a three-dimensional feel. But the rhythm section, no. You want to keep that as tight as possible."

Pettibone agreed there are limitations: "I think it would work great for albums. For 12-inch singles, I don't see it as necessary. . . . The only place I don't see it working at all is classical."