Microphone Phase Detector and Indicator

Parker Foresman

Senior Capstone Project

Union College

Class of 2018

When recording music using multiple microphones, the sound quality may be limited due to phase cancellations between microphones. These cancellations occur due to differences in microphone distance from a common sound source. When the positive and negative portions of a sound signal are added together, cancellations at certain frequencies can occur, resulting in a dull sounding recording. Using phase correlation hardware, this project aims to give audio engineers an indication of any phase cancellation problems that may be present in a recording setting prior to recording an instrument. By doing so, the device will assist the user in obtaining quality sounding recordings.

A project demo can be seen Here. This demo is done using a 400Hz sine wave and two microphones. Notice that as one microphone is moved away from the other, the bar LED indicator shows increasing phase cancelation. 17 seconds into the video, the bar LED begins increasing. This means that the two signals captured are coming back into phase.