Acoustic Echo Cancellation (AEC)


When QSC launched the Q-Sys platform back in 2009, we set a new standard for sheer processing power by creating a revolutionary series of super-DSP engines based on an Intel CPU platform.

Now QSC has set another new standard with their Acoustic Echo Cancellation, by leveraging the vast processing power of these super-DSP engines, and allowing the integrator to drag-and-drop abundant AEC components directly into their design.  No longer is the integrator constrained by using hardware-based fixed-path AEC – they now have complete flexibility to place AEC anywhere within the digital signal path of a Q-Sys system. 

The chart below demonstrates the copious AEC channel count available with each Q-Sys Core.  The AEC functionality can operate as a single channel component, or a multi-channel component. Numerous components can be added to a single design.  Furthermore each component offers the option of a 200mS tail length (for typical small rooms) or 400mS* tail length (for large reverberant rooms).


How AEC works:

The Q-Sys multi-channel Acoustic Echo Cancelling (AEC) component is used in conference rooms, courtrooms, boardrooms, lecture rooms, and other installations where people call in from remote locations. The remote caller’s voice comes from the “far end” and is broadcast over loudspeakers into the “near end” room. The sound is picked up by microphones in the room and echoed back to the remote caller. The purpose of the AEC is to eliminate echoes from the near end while at the same time allowing the far end caller to hear clearly what people in the near end room are saying.


Each microphone in the near end room is plugged into one channel of the Q-Sys AEC component. Each channel also receives the loudspeaker signal that carries the remote talker’s (far end) voice. This is called the AEC reference signal. To remove the echoes, the AEC subtracts a filtered version of the reference signal from the microphone signal.

Additional information about the new Q-Sys AEC component can be located in our Downloads section below.  Here you will find a one-page AEC summary, an extensive AEC White Paper, and the AEC Performance Specifications.


  • Note: Selecting a 400mS tail length for large reverberant room applications, will use up an additional channel of AEC.  For example a three channel AEC component with a tail length of 400mS selected is the equivalent of using six total AEC channels.