LVA Myths


Layered Voice Analysis (LVA) does not utilize the tried and tested and many times validated McQuiston Ford algorithm.

LVA is based on elements of human voice that a person can change at will, namely Pitch and Tone. Pitch and Tone are sensitive to emotions – there is no causal link to Detection Of Deception. An examinee can involuntarily change his tone and pitch due simply to ‘testroom stress’ – which can in turn lead to a false positive or false negative with LVA.

The management of SAPAVSA carried out evaluation of LVA between 1999 – 2002. According to an LVA system, the subject (examinee) was guilty of killing: John F Kennedy; Rasputin; The Tsars; Adolf Hitler; Marilyn Monroe; started and ended world War II; flew a shuttle to Mars and also killed Bill Clinton (still alive when last we looked). Conversely, the examinee was found to be truthful to the questions, “Have you ever committed suicide ?” and “Are you dead ?, when answering “Yes”

Our Overall Accuracy achieved with LVA was less than 20%. Hardly suitable for serious DOD. 

LVA should provide many laughs at a house – party and that is where it should be confined.

LVA systems continually undergo brand name changes. Any handheld product is LVA. Any system providing an instant readout (computerized scoring) is LVA. VP and Bio-feedback polygraph Examiners are taught to handscore charts. Computers have no way of knowing the ambient conditions under which tests were conducted.

The following Brand names are LVA
  • Truster Pro
  • Tipi
  • Vericator
  • Vypre
  • TVSA-3
  • X-13-VP

Members of the public should exercise their rights by inquiring what type of VP is to be utilised before agreeing to be tested. Insist on genuine VP. The highlighted brand names below

Traditional Voice-polygraph (VP) evolved from the Psychological Stress Evaluator (PSE) The PSE 1000 & 2000 were analogue machines developed by a trio of scientists (McQuiston, Ford & Bell) trading as Dektor Enterprises.

The heart of the PSE was the algorithm written by McQuiston & Ford. Charles Humble was associated with Dektor. He left to start up NITV and sold the CVSA – a laptop loaded with the VP algorithm.

An Associate of Dektor’s Alan Bell, one William Ames, acquired the algorithm and marketed VP under the name Diogenes Lantern.

Gary Baker was employed by Diogenes. He left their employ and marketed a manual VSA program under his own name Baker FVAS , which he later renamed Expertos.
Dektor’s newest product is branded PSE5128. It is a manual program requiring laborious pre-recording of entire test, thereafter feeding the sound into a laptop, for further manual analysis.

Anything other than AVSAPRO and CVSA is not Voice Polygraph. No person should allow themselves to be tested by any other Voice Polygraph or Voice Stress Analysis system.