J P French Associates are experts in authenticity testing of recordings.  Typically we are asked to establish if a recording has been edited or tampered with.  In some cases, we are instructed to investigate the circumstances in which a recording was made or assess whether it was likely to have come from a certain device.  This can involve physical or digital evidence.


There are many techniques that can be used to establish if a recording has been edited, and our audio experts have experience of using a wide range of authentication techniques.  These can range from physical examination of audio tapes using specialist equipment to computer-based digital audio analyses.

ENF system

We are the UK’s only independent forensic service to have a working ENF (electrical network frequency) database system.  The ENF system is a cutting-edge forensic tool that records the instantaneous frequency of the UK mains power supply and compares it with moment-by-moment fluctuations in the mains hum found in digital forensic recordings.  This can reveal the exact time a recording was made and can also be used to detect editing.


The format of authentication reports depend on the analysis required and the processes used by our analysts, who have many years of experience in producing reports and presenting evidential findings.  Reports will comply with relevant legislation in the jurisdiction.

Case examples

JPFA have carried out a number of authentication cases, some notable examples are included in our case archive.

Further information

BBC article on ENF [12.12.12]

Other terms include: verification, editing detection