Dynamic microphones use magnetic elements that convert sound into small electrical signals in a manner that is basically the reverse of that used by loudspeakers to convert electrical energy into sound. Membrane motion caused by sound pressure is sensed by the electronic circuit and converted into a usable electrical signal. Condenser microphones have smooth, extended frequency response and a clarity and definition not usually found in dynamic microphones. They can also be miniaturized, making them especially suitable for clip-on use. Both dynamic and condenser microphones can be designed to be directional or omnidirectional.
Directional microphones receive sound more efficiently from one direction than from others.
This is useful when it is desired to pick up sound from greater distances or to de-emphasize unwanted external sounds. Omnidirectional microphones receive sound equally well from all directions. This is desirable in many situations, such as for clip-on microphones which cannot be directly in front of the mouth. Handheld transmitters almost always use directional vocal microphones, which may be either dynamic or condenser. In many cases, a particular wireless system is only available with one type of handheld transmitter and one type of microphone element, usually dynamic.