An AEC solution that is poorly designed or inappropriate for the location will not provide these benefits and can even degrade audio quality significantly. There are many AEC solutions available, ranging in price from several dollars to several thousands of dollars. There is also a broad range in quality and performance. This paper outlines some guidelines for determining the performance needed in a given location, judging the performance of an AEC solution based on specifications and listening

If it does not choose properly, speech may be distorted by the AEC or the canceller may go out of convergence. Since modes change frequently during conversations (especially when there are more than two people participating), state machine performance is extremely important. The basic factors of the state machine’s performance are 1. The accuracy of determining the correct state 2. Impact on the signal if the wrong state is selected 3. How gracefully it switches between states. The two most crit

• AEC for medium to large rooms - these products may contain microphone inputs and record inputs / outputs in addition to the standard audio inputs and outputs required for AEC operation. • AEC for videoconferencing - these products may contain multiple inputs and outputs, or incorporate “phone add” modules to permit the addition of a 2-wire conference (telephone call into the videoconference). Step 2: Eliminate the products that don’t meet G.167 or the tail length needs of the application. It i