Are the loudspeakers devices that use a current? ctrica variable to control the field magn? tico of a coil to create sound. Does the sound happen when the field electromagn? tico variable interact? to with the field magn? tico of a im? permanent n and vibrations and waves of sound are created.

* Fine cardboard

* Cart? n

* enameled Wire Not 28

* sticky Tape

* Scissors

   It takes a piece from fine cardboard and it draws up a c? rculo of 11 cm of radio to make the cone of the loudspeaker.

After to cut the paper disc, we formed a cone, we overlapped about 3 cm of one of the edges.



We take a piece from fine cardboard of 12 cm of side. We draw up two cs? rculos and we divided in two halves as it is seen in the photo. To the center we held with glue a im? circular n. One is due to place between the im? n and the fine cardboard a piece of cart? indented n as spacer.


    Does Enrrollamos wire fence enameling Not 28 around a cylinder or on a bottle for roll of pel? cula (or on a great battery). We must use of 3 to 5 ms of enameled wire. The one that we have by hand, at the most thin can be used better the wire. In the ends we must leave about 15 cm.

Soon we assured the coil enameled wire making pass the ends as is seen in fotograf? a. It binds the ends to clear the enamel.


   It holds in cone to the base squared with the help of sticky tape and glue. It places to the center of the cone the coil and assures in his place with sticky tape and glue.

   It cuts a fine cardboard piece and it doubles soon in the form of L perforates some holes, holds the loudspeaker as it is seen in fotograf? to and you do to pass the ends of the coil through the holes.

   With this already we have finished the loudspeaker.

NOTE: Does this loudspeaker have a very low impedance (or resistance) reason why can gives? ar some equipment as amplifiers, etc. Because it is an experimental loudspeaker only for demonstrations does not have a very good volume of exit. It is recommended to use a circuit as a generator of tones to use it in the demonstrations.