Post by petr pazourek on Sept 25, 2019 5:22:27 GMT -5
Hi, I have tried to analyze a biquad filter. Its params are: a0=0.2, a1=0, a2=0, b1=0, b2=0.98, Fs=310Hz. The filter is a band pass for 77.5Hz. The magnitude of this filter is shown as expected. However the phase is slightly different than showed me two other tools. The other tools showed me the phase started at 0rad, then went up to pi/2, at the center of band pass frequency went through 0rad to the -pi/2 and than returned back to 0rad. The DSPLink starts at pi/2 and ends at -pi/2 and the 0rad crosses before the center of frequency. What could be wrong?