[AG-TECH] AG Echo

[Jason Bell]

G'day Chris

>From my experience, both the XAP400 device and the audio machine can
cause these problems.

Some of the suggestions I would investigate is:

Audio Machine

*	If the output PCM / master output levels are too high, I find
these levels can effect the echo canceling.

ClearOne (XAP400)

*	Ensure you have echo canceling enabled on your inputs
(Particularly on your inputs that have mic's connected to them.)

*	As with the audio machine levels, if you have the gain levels
set too high, it also can effect the echo canceling.  (But generally,
you tend to start hearing yourself back in your own speakers)

In my opinion, these settings can be quite fiddly and takes time to
adjust to the correct settings.

Also, you might find the following useful to help you test the machine
personally as well
(http://agcentral.org/help/tutorial/qualityhelper/qusound).

If you have any further problems, please don't hesitate to contact me.

Hope the above helps,
Jason.


-----Original Message-----
From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov] On
Behalf Of Chris Kendrick (VPAC)
Sent: Thursday, 15 December 2005 3:01 PM
To: ag-tech at mcs.anl.gov
Subject: [AG-TECH] AG Echo

Hi all

This is my first post to the ag-tech mailing list =)

I have recently taken over from Nelsie Fernandes at the VPAC Access Grid

We recently had a HW failure on our audio machine (vidio reception, 
transmission, and sound are all on different machines)

Since I brought the audio machine back up i have been causing echo to be
heard 
at the other sites.

My question is, can echo like that be caused by the audio machine not
being set 
up right or is the echo canceller (ClearOne XAP400) entirely to blame?
(some of 
the settings may possibly have been mucked up while myself and others
were 
fiddling around trying to find why our sound system stoped working)

Any advice greatfuly received.

Chris Kendrick
VPAC