Hi, why the magnitude response plot of filter is usually being normalized? What is mean by normalized plot and what the advantages of using normalized plot in the magnitude response plot of filter? Thanks

 

There are two magnitudes that are normalised: The impedance magnitudes of the RLCs are normalised to give a cutoff/centre frequency of 1 radian per second, and sometimes (but not always) the output amplitude is normalised to a gain of 1. In the latter case it's just to make comparisons between different graphs easier, either in the time domain in terms of risetime and overshoot, or in the frequency domain in terms of gain ripple.