[Asterisk-Users] PRI and echocancel

[Eric Wieling]

Tobias Jönsson wrote:

> If you need echo cancelling on the PBX PRI depends on the phones used on
> that PBX. If they are all digital and they do not introduce any echo you
> will not need any echo cancelling.

The outside phone will still (usually) be analog and cause echo.  So 
unless you are only calling other VoIP or cell phones you still need 
echo canceling when using PRI.