Looped-Back Audio in Multi-Site Installations
Echo may occur if audio is looped back to the originating site through the transmission network. In the example below, the MCU does not perform a mix minus on the audio coming from all the connected sites. Each site will receive a mix of the audio from all sites, including itself. This looped back audio will be delayed by several hundred milliseconds (since it has been encoded and decoded twice). It will also be a very clean, loud echo since the site is receiving exactly what it sent out.
The EF1210TEC solves this problem by comparing the audio which is sent by a site with the audio that is returned to the site via the master mix. It removes copies of the local audio but leaves the other signals intact.
Click here for an explanation of transmission delay.
Click here to download
the EchoFree™ EF1210TEC spec sheet in
Acrobat PDF format. (2 pages, 217K)
