A magnetic transducer for reading magnetic information from a magnetic support such as a disc or tape which moves before it, comprises a magnetic circuit formed of two thin layer polar pieces having a gap at one end and means coupled magnetically to the circuit for transformation of magnetic flux loss of information into an electric signal. The pole pieces comprise at the level of the gap a central part bounded by two lateral parts spaced such that the magnetic coupling between the central parts is very much less than the magnetic coupling between the corresponding lateral parts of the pieces. The gap disposed between the central parts is larger than the gap of the lateral parts. There is a substantial reduction in Barkhausen noise and parasitic edge effects over conventional transducer constructions which is obtained by making the thickness of the pole pieces of the transducer substantially greater in the area of the geometric path Lpm than at the lateral portions beyond Lpm.