Double Talk x Echo

[pborelli]

I have a problem with echo not being cancelled during double talk. When the two parties talk together, echo becomes very annoying. But echo is perceived only by one of the users, let's call him "A". "A" is connected to a 1750 (through a PBX) and "B" to a 5350 (through the PSTN). During double talk, "A" perceives a lot of echo, but "B" perceives nothing. Also, sometimes, instead of echo, "A" doesn't hear "B"'s voice (during double talk) and, so, there's no echo too.

Does anyone shed light on this issue?

Thank you,

Paulo.

[asandborgh]

The echo problem is actually at the 'B' end of the circuit. Cisco has a good white paper on this (you will find your condition described and explained...almost exactly). It is titled "Echo Analysis for Voice over IP" and it is dated 6/22/2001. You should be able to find it on CCO...Unfortunately I cannot remember the path.

Have Fun...

[pborelli]

Yes, I know about this document. But I'm trying to find a more pratictal insight on this issue, like what people have done in real situations. I'm yet studying how the canceller detect double talk, what does it do, how can I overcome the problems.

Thank you,

Paulo.

[jaiello2000]

I have delt with this a lot. I decided to use an after market echo canceller with a longer tail coverage and more effective double talk cancelation.