You may have heard how Lincoln Center Festival audiences are gliding into the sordid world of the Bernd Alois Zimmermann opera Die Soldaten, thanks to a movable seating area at New York's Park Avenue Armory.

Equally dramatic was the Warsaw-imported adaptation of Shakespeare's Macbeth, presented by St. Ann's Warehouse in an open-air tobacco warehouse between the Brooklyn and Manhattan Bridges, with the audience traveling aurally thanks to sophisticated sound design and individual headphones.

But can anything top Helicopter String Quartet, a DVD about Karlheinz Stockhausen's work of the same title with each player performing in a separate helicopter?

What feats! Imagine the technology involved in piping the sounds made by the airborne Arditti Quartet into a Dutch concert hall. Tons of track and related machinery were imported for the staging of Die Soldaten. And Macbeth was staged in a place where the rumble of New York's traffic-packed bridges had to be overcome.

In every case, though, the audience's encounter with the music or theater at hand was hugely intensified. Similar effects might be accomplished more simply in the future now that we know the artistic destinations that are possible with such stage mechanisms - destinations that weren't what I initially anticipated.

Die Soldaten reverses the equation of Franco Zeffirelli extravaganzas at the Metropolitan Opera: Instead of having the coup de theatre onstage, it's in the 1,000-seat raked seating area that moves the entire length of the long, narrow platform on which the opera is staged. The actual presentation of the story about gentlemen soldiers riding roughshod over anything that gets in their way was fairly straightforward, right up to the climax, when a woman who is loved and discarded by several male characters is brutally raped by that ultimate figure of male benevolence, Santa Claus.

That, plus the little-known opera's dense, ultra-modernistic score wouldn't usually be an audience magnet, especially with ticket prices as high as $250. But operatic adventurers were rewarded by an experience that took them into the thick of the opera, often only a few feet away from the singers and with instrumentalists on both sides. Music that usually sounds like undifferentiated anguish emerged, from this inside viewpoint, rich in variety, from dissonance inspired by Berg's Wozzeck to the more amorphous and delicately colored manner of Pierre Boulez.

Ultimately, though, Die Soldaten, which has surfaced fitfully since its 1965 premiere, fails to emerge in this setting as a masterpiece. The opera's characters are mundane or reprehensible, and not in ways that tell us anything we don't know. They also lack the stature that gives them life outside the social commentary.

Yet you can't say that director David Pountney, conductor Steven Sloane, designer Robert Innes Hopkins, or the valiant cast headed by Claudia Barainsky, Hanna Schwarz and Kathryn Harries has expended huge efforts on a piece that doesn't deserve it. Though not a great opera, Die Soldaten, in this particular package, was a great experience, partly because you were unmoored from any conventional point of reference in ways that wouldn't be possible with a more familiar opera.

The fact that the audience traveled into the middle of the piece delivered the immediacy of the rehearsal-hall experience (which many people in the opera business prefer to the actual opera house), but with the extra power of fully realized characterizations, lights and costumes. Such jolts are invaluable in a world where the same operatic masterworks are examined time and again, each new experience judged all too strictly by previous ones. Subsequent performances of Die Soldaten are scheduled for today, Friday and Saturday.

The Polish Macbeth (unfortunately now closed) was similarly wrenching. The modern-dress, graphically violent production by Grzegorz Jarzyna audaciously added new scenes to Shakespeare, establishing the title character as a renegade who had little support from his higher-ups, and thus had fewer reasons for loyalty.

The sound design - and the headphones that came with it - were full of atmosphere while also allowing actors literally to whisper in your ear. So when the pathetically undone Lady Macbeth appears to urinate onstage while sleepwalking, you feel her abject misery. Like Die Soldaten, Macbeth was swift, seamless theater that gave you little room to catch your breath and be an outside observer. In a world where theater often behaves like a well-mannered guest, this production - with the menacing rumble from the nearby bridges - seized you as surely as Macbeth did his onstage enemies, and suggested, in this time of war, how our enemies have it.

But let's not start proclaiming that the future of the performing arts lies in warehouses and armories. In the Helicopter String Quartet DVD, the always-experimenting, recently deceased Stockhausen started with a simple desire to have musicians fly, with all the transcendence that implies. Later, he admits that the machinery needed to do so took him away from that - with music that has musicians dueting with helicopter sounds.

Yes, there are audience giggles on the DVD and the composer is annoyed. His pieces always take years to sink in (I didn't get this one). But with an apparatus like this, how often can we expect repeat performances?