[Asterisk-Users] Why echo occurs

[Steve Underwood]

Robert Hajime Lanning wrote:

><quote who="Steve Underwood">
>  
>
>>Wrong. Look at any cellular phone or IP phone. They all have echo
>>cancellers. If you switch these cancellers off the results are
>>generally bad. What they need to remove is the acoustic spill
>>from the earpiece to the mike. This can be a surprisingly strong
>>signal.
>>    
>>
>
>While acoustic "spill" can be an issue, I do not believe it is
>the primary source of 90% of the echo experienced.
>
>I do not know of any IP phone that contains an echo canceler other
>than speaker phones.
>  
>
Can you show me an ad for an IP phone which doesn't say it includes an 
echo canceller? A real phone, I mean. Not some thrown together half 
baked softphone, many of which do a very poor job.

>Find a situation where you think the echo is acoustic spill, then
>try it with a hands free head set.
>  
>
Sounds like you haven't worked with this very much.

>If you notice, the echo is a repeat once type of echo.  Not the
>fading echo of a loop, that acoustic spill would cause.
>  
>
Who introduced a loop into the discussion?

>All the echo that I have been talking about, you hear yourself once,
>just delayed.
>  
>
Yep. That's the way they usually are.

Regards,
Steve