In London in the early '80s, you didn't necessarily have to be a musician to break into the music scene.

It was the post-punk period, when groups like the Human League, the Smiths, Echo and the Bunnymen and Depeche Mode made "synth-pop" or "technopop," a sound based on the synthesizer and simple vocals.

Many groups, like the Human League, were short-lived. Others, like Depeche Mode, are still around, developing the multi-track studio mix by adding both more computerized and traditional acoustic instruments.

"We like the challenge of using the latest technology," says Depeche Mode's Alan Wilder, "and we like to explore every possibility to find the sound for a song."

This means taking the time for experimentation. The group brings in session musicians to add basics like drums and acoustic guitars as well as modern components such as analog synthesizers and other electronic keyboards.

The latest album, "Violator" (Sire), took nearly a year to complete. But then, all that work isn't just for the record.

On stage, Wilder, Andy Fletcher and Martin Gore play synthesizers and Dave Gahan sings. That's it. The rest is produced by 12-track tapes.

"They have most of the rhythm elements and sequences we can't play," Wilder explains matter-of-factly. "That's the way we've always worked."

So it's a polished production. But it's also a constricted show that can become stale. "It's hard sometimes to go out on the road and perform the same show 100 times," says Wilder.

Depeche Mode performs at Merriweather Post Pavilion Wednesday night at 7. Tickets are $17.50 and $22.50 and are available at Ticketron or by calling Phonecharge at 1-800-543-3041. For information, call 982-1800.