JonBenét Ramsey

Enhancement and analysis of the infamous 911 call.

David Mariasy from Audio/video forensic and restoration associates worked on this case

At the end of June, 2003, NBC news requested David Mariasy of Team Audio to enhance and analyze parts of the 911 call from the JonBenét Ramsey murder case.

Many theories have been made as to what happened to JonBenét. One of these theories involves what was actually said during the inaudible parts at the end of the original 911 call.

NBC aired their report on the analysis of the 911 tape by audio experts on July 9th, 2003, which names David Mariasy as one of their experts.

The Toledo Blade issued an article on July 9th, 2003 from an interview they conducted with Mr. Mariasy about his involvement in the case.

Mr. Mariasy’s conclusion was that the alleged dialog at the end of the 911 call was not substantiated.

“After two days of analysis, Team Audio determined the only conversation on the tape was between Mrs. Ramsey and the 911 operator.” (, 2003)

This tragic case has been documented intensely, for more information on the 911 call please see the JonBenét Ramsey Case Encyclopedia.


To analyze the original 911 call, it first had to be enhanced to clear up as much of the background noise.

This 911 call was recorded on cassette tape, and every cassette tape has some mechanical noise from the recording device as it records the audio. This mechanical noise can be removed by eliminating the 50hz or 60hz hum produced by the recording device.

Static background noise can be recorded from any number of sources such as a furnace blowing or appliances running.

Background noise can cause a problem in identifying voices that are very quiet or soft compared to the noise. This is why audio experts are contracted to remove background noise, it is a delicate process. If too much noise is reduced, it could also reduce the desired conversation needed to be enhanced.