Abstract: A system for processing signals produced by magnetic flaw detection apparatus having facility for examining objects in the course of transport thereof at speeds varying from a prescribed slow speed to a prescribed high speed, with transport frequency thus being within a first frequency range. The system comprises first circuitry for detecting the speed of transport of an object under examination and generating output signals indicative of the detected speed and extending over a given characteristic range correspondingly with the first frequency range. Second circuitry is provided for receiving the first circuitry output signals and transforming the same into a second frequency range substantially expanded as compared to the first frequency range.