We present results on Barkhausen noise power spectrum in polycrystalline 3 % SiFe, measured in the central part of the hysteresis loop as a function of permeability µ and magnetization rate I, in the range 2.6 x 103 ≤ µ / µ0 ≤ 5.5 x 104, 1.5 x 10-4Ts-1 ≤ İ ≤ 5 Ts-1. The parameters describing the spectrum shape exhibit definite power law dependences on both µ and I