L2 Lip Microphone (incl. equaliser) in fitted case. Ser: 144, BBC Patent Application No. 24513/52. Commentator's lip microphone. For sports commentaries and anywhere there was a noisy background, it was necessary to speak very closely into the microphone and even then the listener could often hear much more of the background noise than was really wanted. In 1937 the BBC designed the original lip microphone, (model L1), to overcome this problem. A metal guard ring at the front of the microphone gives a precise speaking distance of 2 1/2 inches when pressed against the top lip. For this reason these microphones became known as "lip microphones". Sounds coming from further away than this distance tend to cancel each other out. The design was improved in 1951 with the introduction of this microphone, (model L2). By 1954, ninety-six L2 Lip microphones were in use by the BBC. The design has since been refined further.