[AG-TECH] about echo cancellation equipment

[Rick Stevens]

Jay, let us know what you find out..

At 07:37 PM 5/3/2001 -0700, Jay Beavers wrote:
>An interesting feature of Windows XP is echo cancellation in software.
>
>I haven't played with this yet, but it is exposed via the DirectSound 8
>API.
>
>  - jcb
>
>-----Original Message-----
>From: Robert Olson [mailto:olson at mcs.anl.gov]
>Sent: Thursday, May 03, 2001 7:23 AM
>To: lujian at nlsde.buaa.edu.cn; ag-tech at mcs.anl.gov
>Subject: Re: [AG-TECH] about echo cancellation equipment
>
>I'm of two minds on this. It would be cool if the echocancellation in
>the
>chips worked well -- it would make simple installations work nicely
>(casual
>audio use in an office PC, for instance). However, for an AG node with
>multiple microphones it would pose a problem, since the cancellation
>would
>likely suffer in a multiple microphone system. This is the difference
>between the chip-based systems and the Gentner: the Gentner does echo
>cancellation per-microphone.
>
>Another interesting variation would be the use of multiple audio cards,
>one
>per mic -- at $100 a pop for the cards, it would be less expensive. It's
>a
>question of complexity vs price. The Gentner also does good things with
>its
>support of the balanced audio connections, connectivity to other
>devices,
>phone, etc.
>
>Do you know if the echo cancellation options/control show up in the APIs
>
>for programming the sound cards?
>
>--bob
>
>At 04:48 PM 5/3/2001 +0800, lujian wrote:
> >         I heard that soundcard powered by Crystal/Cirrus SoundFusion
>DSP
> > (digital signal processor) can do echo cancellation work . Is it
>possible
> > that we use such a soundcard as a second choice of Gentner system?
> >         And is there anyone who can tell the difference between the
> > card-based echo cancellation and Gentner echo cancellation?
> >
> >some reference sites:
> >http://www.voyetra-turtle-beach.com/site/press/releases/santacruz090100
>.asp
> >http://www.cirrus.com/design/products/overview/index.cfm?ProductID=42