There are many diffrent kinds of noise in the world of forensic audio but we are concerned with mainly 2 types in the process of removal and enhancement. These noises are called Impulse noise and Non Impulse noise. Waveform reconstruction is the basis for Impulse Noise removal. The original recording is digitized and analyzed with the computer. Impulse noise is recognized with software as it peaks and is compressed or removed depending on the method.

Non Impulse noise is removed in a similar way. Utilizing sophisticated software it is removed or reduced by sampling the offending sound and adjusting the software to recognize its unique pattern. Sometimes it is significantly reduced and other times it is impossible to remove it all without damaging the wanted signal. In that case some must be left in. Usually it will take a combination of methods to achieve the desired end result. That is why a 30 min tape for instance can take hours to analyze and process. This combination of engineering skills and computer techniques as well as realtime processing can in most cases achieve positive results. This all depends on the original recordings state or condition.