[AG-TECH] Echo Cancellation hardware

Todd Zimmerman toddz at sfu.ca
Tue Feb 21 23:01:37 CST 2006

Hey Chris,

Yes, we use the Biamp Audiaflex for our theatre and it seems to work well.

Best feature is the configurability.  It has a GUI front end that allows you to 'drag and drop'
components right into the signal path.  So, for any input, you can drag components such as an eq,
gain, gate, compressor, leveler etc etc - plus any combination of mixers (matrix or combiners, etc).
 VERY configurable.  With our theatre we have easily lots of inputs/outputs that we run through a
hardware switch then into the Audia and this system handles it all very well.

On the down side - the one critical issue we have experienced is a signal 'propagation delay'.  By
adding more and more components on to the signal path, you increase the signal propagation time
through the unit.  Plus, when you use echo cancellation in the signal path, it introduces a 20ms
delay into the system on its own.  Currently, our delay seems to be about 25-30ms, and while this
mostly unnoticeable and doesn't cause many (any?) problems for the remote sites - when we take a
feed of the mics for local reinforcement to the local speakers, it is quite noticeable and
distracting.  This is especially true for the speaker's themselves - with the delay being quite

We have, however, come up with a work around to this issue.  Our mics are all wireless and go
through a single (multi module) wireless receiver unit - and this unit has a 'mic mix out' which can
be set to line level.  So I've taken a separate line level mix of all the mics and fed that _also_
into the Audiaflex (into on of the Line Level inputs - bypassing the Echo Reference Input and thus
the majority of the delay).  Works Great.

All in all I'd say it does a pretty good job and is nicely configurable.

One other note - I've called their support line twice - and both times was on the line with a
_knowledgeable_ human within a minute or two.  Very helpful.

Feel free to email directly if you want more info, etc.


Collaboration & Visualization Technician
WestGrid - www.westgrid.ca
IRMACS - www.irmacs.com
Ph. 604.268.6979
Todd Zimmerman - toddz at sfu.ca

Brian Corrie wrote:
> Hi Chris,
> I believe we use one of these in our lecture/visualization theatre that
> is AG enabled. Not sure of the exact make/model, but I believe it is a
> Biamp Audiaflex. I have cc'ed Todd on this as he will know more.
> We are pretty happy with it, although again, Todd can comment in more
> detail. I think it has more processing capability and flexibility than
> the XAPs.
> Brian
> Christoph Willing wrote:
>> Has anyone used the modular "Audiaflex" echo cancelling system from
>> BIAMP (http://www.biamp.com/index.php?pg=audia/index)?
>> Apparently you choose various combinations of input, output, echo
>> cancelling and phone input modules to suit your needs. The salesman
>> assures me its better than an XAP400 (which he also sells) and that a
>> configuration comparable to an XAP400 is cheaper than the XAP400.
>> chris

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