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<DIV><FONT face="Courier New" size=2>Hello All,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>The solution which is good enough for me at
the moment, is James Harper's echo preload patch. The echo is reduced to the
minimum from the start of the call. I just need to reduced the rxgain to make it
more unnoticeable.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I implemented on SVN-branch-1.2-r8445 by
hand yesterday, but I got no audio this morning. After updating to
SVN-branch-1.2-r8666, the audio came back, but also the echo. So I decided to
use Asterisk 1.2.1 and put in the patch.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Cheers,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Anto</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=aryanto.rachmad@chello.at
href="mailto:aryanto.rachmad@chello.at">Aryanto Rachmad</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=asterisk-users@lists.digium.com
href="mailto:asterisk-users@lists.digium.com">Asterisk Users Mailing List -
Non-Commercial Discussion</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, January 23, 2006 12:13
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Asterisk-Users] Reducing
echo on FXS port</DIV>
<DIV><FONT face="Courier New" size=2></FONT><FONT face="Courier New"
size=2></FONT><BR></DIV>
<DIV><FONT face="Courier New" size=2>Hello Giovanni and
everybody,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Thanks a lot for your
suggestion.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Unfortunately, that does not help. With
READ_SIZE=16, I got vibrating voice on the speaker phone. With READ_SIZE=80,
the voice came back to normal and the echo is more reduced but still
noticeable. I finally changed it back to 160 as it seems to affect a lot of
things in chan_zap.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I am sorry that I didn't properly explain
the setup I have. I think this issue happens because I use wireless handset.
Here is my actual setup:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>
--------------- out
------------<BR>
| |
<--- | |<BR>Wireless
handset <--> Base phone <--> FXS (TDM400P) <--> | ZAP
Channel | | Asterisk |<BR> (Mic
muted)
| |
---> |
|<BR>
--------------- in
------------<BR>
^<BR>
Monitor()</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>The delay between the original voice
going out from asterisk to the phone, and its echo coming back to asterisk is
about 104 ms, assuming that Monitor() application wrote both files at exactly
the same time. How did I find that? I loaded the "in" and "out" files created
by Monitor() application into Audacity (audacity.sourceforge.net). I could not
find any other method to find this delay. Does anyone know a better and more
accurate method?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>When I did the same thing using X-Lite
with below setup:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>
--------------- out
------------<BR>
| |
<--- | |<BR>PC
(X-Lite) <--> | SIP Channel | | Asterisk
|<BR>(Mic muted)
| |
---> |
|<BR>
--------------- in
------------<BR>
^<BR>
Monitor()</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>There is no sound at all on the "in" file
created by Monitor() application, indicating that there is no echo at all as
the microphone on X-Lite was muted.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Since the echo on FXS is consistent,
there must be a way to eliminate it. The question is how? I think it can not
be done only by changing the configuration parameters related to echo,
especially with this huge delay.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Do you have any other
suggestions?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Cheers,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Anto</FONT></DIV>
<DIV><FONT face="Courier New"
size=2></FONT> </DIV></BLOCKQUOTE></BODY></HTML>