New microphone can hear any sound at outdoor sports venues

The large yellow circle attached to the bottom of the Los Angeles Lakers Jumbotron is a new super microphone that can hear anyone on the basketball court with perfect clarity — even players chewing bubble gum.

The microphone is called an AudioScope and could radically transform sound for sporting events. Developed accidentally when two former University of Oslo physicists — Morgan Kjølerbakken and Vibeke Jahr — were working on sonar technology, the new device is a circular array of 315 microphones and a wide-angle camera that hangs above sporting venues.

It can be used to capture audio from any chosen sound source, like a zoom lens on a camera. With sophisticated signal processing algorithms and so many individual microphones, the AudioScope can isolate sounds and make them clear — even in a noisy environment.

Viewers can hear a player's voice as he scores during a football match on television. Or one could hear every question at a news conference without the use of handheld or shotgun microphones. Such a breakthrough in sound quality could intensify the action of the game and add an entire new dimension for the viewer.

Based on the same principle as sonar, the AudioScope microphone can be zoomed in to listen to any individual who happens to be playing, coaching or refereeing. Because the camera is also fixed, it can be calibrated to zoom in to any location within its range. In addition to the Lakers, the system is currently being tested out in some basketball and soccer arenas around the world.

The system's software determines where the desired sound is originating from and then calculates how long it should take that sound to reach each individual mic overhead. It then synchronizes the conversation, making any spot audible even in a crowded stadium.

"If we correct the audio arriving at three microphones then we have a signal that is three times as strong," Kjølerbakken said. Doing the same thing with 300 microphones can make a single conversation audible even in a stadium full of sports fans.

An operator uses the AudioScope control station to remotely zoom in on the sound. He monitors the picture on a screen and moves the cursor to any audio source. The trackball is used to follow moving objects, and the jog wheel is used to rewind the tape for replays. The system supports multiple output channels, and the operator can select up to five audio sources simultaneously.

Kjølerbakken and Jahr have now patented the device and founded a company, Squarehead Technology, based in Oslo, Norway, to develop their idea. The most obvious application is in televised sports, and the company has been working with basketball and soccer teams to test it out. The response has been good, Kjølerbakken said, although some players aren't pleased by the idea.

The new microphone is also envisioned as an addition to video teleconferencing equipment. Squarehead recently announced that a system is now installed in a 175-seat auditorium at the Max Planck Institute in Munich.

A video demo can be seen at www.squarehead.no/video.html.