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Monday, July 10, 2006

Designer speakers

Loudspeakers can be ugly boxes that ruin the aesthetics of a room. So to transform them into a more attractive feature, an inventor in California is patenting a way to make a speaker from an ornamental container, such as a vase or sphere.

First, the container is filled with ferrofluid – an oil containing nano-sized magnetic metal particles. A large bar magnet is then hung in the middle of the fluid, and a coil wound round the outside of the container.

When a music signal from an amplifier is fed through the coil, it creates a pulsating magnetic field in the ferrofuid, which interacts with the static magnetic field around the bar magnet. The magnet vibrates, causing the ferrofluid to vibrate, and with it the walls of the container. As a result, the ornament radiates sound all around the room.

If the speaker is made from a transparent container, and a light emitting diode is also placed inside the fluid, the device will emit a glow that throbs in time with the music. Just what the DJ ordered.

Read the musical vase patent here.
The mass/density of the vase may be too much to efficiently convert all energy coming from the amplifier into sonic energy. A conventional speaker itself is only 15% efficient. The freq bandwidth of the output may be very limited due to the properties of the vase. will it be able to produce a 30hz signal efficiently?

would this mean its an omni-directional speaker? what about stereo imaging?

The concept is very innovative.
Ferro-Fluid may damp the energy excessively.
By Anonymous Anonymous on August 11, 2006 3:33 PM  