Question

You are using an 8 th order low-pass filter. Determine the roll-off achievable in the stop band, in dB/dec, and determine the phase shift in the stop band, in degrees. What is the advantage of using this filter compared to a second order low-pass filter?

Answer 1

Answer: The complexity of filter is the order of the filter. Greater the order of the filter, more efficient the filter is. Roll of value of one filter is 20dB/dec. So the roll-off value of 8th order filter is 160dB/dec. 8th order filter is more efficient than the second order low-pass filter.