A microphone converts sound energy into an electrical signal to enable it to be recorded or transmitted to a remote location. It has already been mentioned that microphones also pick up unwanted sounds together with the participants’ voices. If these unwanted sounds are significant they will interfere or even completely obscure the desired parts of the sound. The correct choice of microphone and its position in the room are vital to achieve high quality sound. The conference environment will also influence sound quality, as has been mentioned above both low ambient noise levels and low levels of echo are essential requirements.