Explaining Forensic Audio (Part 1)
The concept of forensic audio investigation may have become popular in recent years along with the forensic sciences in general but it’s been in practice since World War Field Audio Company II. With audio use in full swing for radio transmissions across long distances, scientists were trying to identify the voices of their enemies among the many radio broadcasts that took place on open frequencies. The work done in forensic audio investigation today is based on the pioneer work of those scientists.
Specifically, forensic audio has to do with any type of audio of an evidentiary nature. In modern cases, law enforcement or other legal professionals (e.g., defense attorneys and prosecutors) will turn to a forensic audio examiner to perform any one of a number of services where audio is concerned.
In many cases these specialists are hired on a contract basis.
While the most common Hollywood portrayal is audio enhancement with a few twists of a knob (if only it were so easy) there is a great deal of work that can be done:
Audio Enhancement – the most common and offered by just about every forensic audio company you can find.
Audio Authentication – geared toward tape and digital formats
There are also a number of other services or procedures that can be classified in their own right as a specialty process or “miscellaneous” in terms of categorization. This article will focus specifically on Audio Enhancement and Authentication.
Audio enhancement is the most common and well known service where forensic audio is concerned.
It’s not likely that one can take a garbled and mangled inaudible conversation and “tweak it” to produce clear speech that is intelligible. While audio enhancement isn’t specifically focused on speech, that is usually the intent behind cleaning up or enhancing audio for legal purposes. It’s a means of reducing or filtering out unwanted noise from a poor recording in order to clear up the speech that’s covered with noise or is a victim of poor recording methods.