The following links & embedded videos contain introductory information on how speakers work from around the web.
Remember that exciters are specialized speakers, and so lack the cone discussed in these resources. Exciters are designed to turn whatever object they attach to into the cone.
- explainthatstuff.com's loudspeaker webpage - clear, basic information on how speakers work, including information on power, sensitivity, and electrostatic speakers.
- Johan Segeborn's youtube video.
- Science Online's youtube video - includes information and a simple speaker building demonstration.