From: cypherpunks@count04.mry.scruznet.com
Date: Mon, 7 Oct 1996 20:33:17 +0800
To: jim bell <jimbell@pacifier.com>
Subject: Re: Voice Stress Analysis of Debates?
In-Reply-To: <199610060428.VAA19939@mail.pacifier.com>
Message-ID: <199610070730.AAA29150@count04.mry.scruznet.com>
MIME-Version: 1.0
Content-Type: text/plain


PSE/VSE etc relys  on a random 8-14 hz fm modulation appearing in the
 the 3rd formant band of the voice... the Dektor PSE retailed for approximately 5k in the early 1970's the hagoth hs-2 was the early 80;s for 2k .. 
I bought 2 VSE units based on a new chip for 89.95 apiece recently...
this was on an article appearing in popular electronics in 1995
no software as of yet and it would be probably a FFT or DFT based algorithm 
running on a sound blaster DSP(hardware DSP only) or as software
 on a fast 150 Mhz + pentium I can give the basic facts known... it is a truth
detector only(not a lie detector), background music shows up a stress...
and scrubbing the modulation shows up as constant stress or "possible decption"
truth is indicated by the modualtion showing up randomly over small increments
of time... the effect is caused by microscopic tremors of the larynx when the 
speaker is relaxed and truthful the larnyx is relaxed and the random modulations
show up,(or the speaker believes what he is saying to be the truth, when lying
or under stress the larybx tightens and the random modulations
disappear indicating stress... it would be  nice to have it in software...
to run on a laptop soundboard and spread to the net as widely as pgp...

   cheers
   a cypherpunk