The present invention guides a talker into a narrow sensitivity region by providing a light that is only visible when the talker's eyes are just above the sensitivity region of a microphone. When the talker keeps the light within his sight while speaking, there is no wavering problem. If the talker cannot see the light, then he is outside the sensitivity region and is alerted to a potential wavering problem by not seeing the light. In this way, the present invention takes advantage of the fact that the talker's eyes are located in close proximity to his mouth. In addition, high frequencies emanating from the mouth are highly directional and applications with speech input, such as speech recognition, function better when these high frequencies are available for analysis.