Saturday, March 10, 2007

The Loudspeaker Part 5

I barely understand how these work so bare with me... part 5 is about the new toys.

To understand how the NXT flat speakers work, it's best to temporarily forget what you know about NXT technology, but the similarities end there. There is no woofer, no tweeter, no crossover. The parts you'd recognize are a magnet, a voice coil and a panel that could be made of aluminum or paper.
everything I wrote earlier this week. The obvious part with an amplifier powering a loudspeaker doesn't change with

NXT speakers operate in a world of psycho-acoustics and math. I'm not a math major so I'll be brief and quote others who are. "The magnet-and-coil assembly moves a microscopic 40 microns, barely nudging the rigid panel to begin a series of bending waves that travel in all directions." the panel drives waves that bend and crossing at angles and at different speeds.

Flat panel speakers are a British innovation. The British firm Verity bought a patent on public address systems owned by the country's Ministry of Defense and modified the speaker to deliver hi-fi sound. They patented this modified version and now licensing it.

But, there is a challenge to that patent. Sound Advance Systems of Santa Ana, California, claims its founder, José Bertagni, patented flat panel speakers thirty years ago. This time frame means that SAS can't claim royalties, it also should mean that Verity's ownership claim is invalid. The technical description in the patent is a prior publication which the SAS is using to attack Verity's claims. Of Course Verity takes the position that the NXT speaker is unique: the NXT speaker panel vibrates over its entire surface. The SAS speaker pumps air more like a piston. Read on: