From owner-freebsd-multimedia  Fri May 17 01:23:19 1996
Return-Path: owner-multimedia
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.3/8.7.3) id BAA26606
          for multimedia-outgoing; Fri, 17 May 1996 01:23:19 -0700 (PDT)
Received: from rah.star-gate.com (rah.star-gate.com [204.188.121.18])
          by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id BAA26600
          for <multimedia@freebsd.org>; Fri, 17 May 1996 01:23:14 -0700 (PDT)
Received: from rah.star-gate.com (localhost.star-gate.com [127.0.0.1]) by rah.star-gate.com (8.6.12/8.6.12) with ESMTP id BAA02406; Fri, 17 May 1996 01:21:40 -0700
Message-Id: <199605170821.BAA02406@rah.star-gate.com>
X-Mailer: exmh version 1.6.5 12/11/95
To: "Christoph P. Kukulies" <kuku@gilberto.physik.rwth-aachen.de>
cc: multimedia@freebsd.org
Subject: Re: full duplex observations 
In-reply-to: Your message of "Fri, 17 May 1996 09:21:10 +0200."
             <199605170721.JAA12644@gilberto.physik.rwth-aachen.de> 
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Date: Fri, 17 May 1996 01:21:40 -0700
From: "Amancio Hasty Jr." <hasty@rah.star-gate.com>
Sender: owner-multimedia@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

> 
> Now after doing some testing with a colleague I found out that the
> nasty echo effect doesn't stem from the GUS wiring mic to local speakers.
> 
> It's simple. You hear your own voice delayed by the packet travel
> time fed back to your opponents mic.
> 
> When he switched off his speakers the echo was gone. So either you use
> a head set on both sides or you refrain from using full duplex.

If you switch the <full duplex> option on vat, it has the interesting
effect of not performing echo cancellation. I believe that the
sgi version of vat or at least the one that I have used in the past
has full duplex enabled by default so switch it off.


	Enjoy,
	Amancio