Echo, I hear a delay in my side tone when I speak?

The 'echo' that you hear is a 30 millisecond delay caused by the DSP (Digital Signal Processor) 'doing its thing'.

In a wired headset you speak into the mike, this signal then travels down the cable into the aircraft's comms module and is 'communicated' to wherever it has been directed (over the radio or to the PAX) and then it comes back up the other cable into your headset speaker as 'side tone'. The whole process is almost instantaneous  (millisecond).

When it is done wirelessly the process needs to be converted to a digital signal and sent wirlessly back and forth to the comms unit and to your headset speaker and it takes 30 milliseconds.  (its about the same echo delay you hear if you were talking in a lounge room)

Now for some people they simply will not notice it or they will only notice it depending on their mood (thats how it works for me) BUT there is a solution and its built into the settings of the EQ-Link.  Its called 'echo cancelation' ....just turn it on.

With this setting, the mike signal goes directly to the headset speaker and also does all that digital stuff  into the aircraft's comms and back to the EQ-Link where it is stopped from coming back to your speaker because its already there.

If you are testing the aircraft's comms it is best to have 'echo cancelling' set to off, this way you can be assured of a complete systems check. if however you get annoyed by the slight delay then turn 'echo cancelling' on.

We are working on reducing the delay but we need faster, low power DSPs

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