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Makers Night Out - Styrofoam Plate Speakers - Aug. 31, 2010
As Seen in MAKE
Last Tuesday we chose this fun and easy project, it's found in Make Magazine #12 on page 131, titled "Styrofoam Plate Speaker".
We had a good crowd of about 12 people including some new visitors who learned about us from the recent KC Mini Maker Faire.
The principles involved in this project are based on simple electromagnetic forces acting between the magnet wire coiled around a paper sleeve. a changing electric signal transmitted through the coil causes it to react against the polarity of the magnet. This causes the plate to vibrate and those vibrations in turn cause the sound waves we hear. The amplifier used this night was recycled from a pair of donor computer speakers.
Everyone had a working speaker by the end of the evening and was surprised at how well they sounded. As we listened to the radio, we heard Steve Siegel say "you haven't heard anything until you've heard the Beatles on Styrofoam".
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