Shhh! The walls are whispering

Deseret News (Salt Lake City), Aug 11, 2003 by David Pitt Associated Press

AMES, Iowa -- Imagine hearing sales pitches as you walk by a glitzy shop window, or soothing dinner music emanating from a tabletop.

Etrema Products Inc. makes Whispering Windows, a device that uses rare metals to turn windows, tables and walls into sound generators.

The conference room at Etrema is filled with the sound of "We Will Rock You" and other Queen tunes. There are no speakers in the room -- only two small, black objects on the edge of a marble-topped table, each the size and shape of a hockey puck.

"The music is actually coming from the table," explains Todd Kreamer, the Ames company's director of sales and marketing.

If you put your hand on the table, you can feel a slight vibration, but the song "We Are The Champions" is clear.

Whispering Windows is an amplifier connected by wires to the two pucklike objects, which contain Terfenol-D, an alloy made from iron and two rare earth metals, turbium and dysprosium. Terfenol-D expands and contracts at various frequencies, allowing sound -- a speaking voice or music -- to come through solid surfaces as if they were speakers.

The device is marketed to retailers wanting to broadcast messages from their storefront windows.

A $20 toy version, called Soundbug, lets you play portable equipment like CD and MP3 players through a car window or other surfaces.

Coming soon: hot tubs that play music.