[asterisk-users] b410p + fax (echo cancellation)

[Lee Howard]

Zoilo Gomez wrote:

> I really don't get it ....
>
> From several emails in this list archive, I had clearly understood 
> that it is important to switch Echo Cancellation off for fax-channels, 
> or faxing would not work properly.
>
> However, faxing (B410P ISDN bridged to TE410P PSTN) seems to work fine 
> with EC at 256 taps on the B410P.
>
> I am confused; can anyone enlighten me?


Echo cancellation does not necessarily break faxing.  However, depending 
upon how it is implemented it can.

In general fax does not care about echo (as long as it is, indeed, more 
of a sidetone than an actual echo), and so it's generally good advice to 
tell people to disable echo cancellation on ATAs and other things when 
faxing is being used on them simply as a preventative measure.

Lee.