# Is it possible to specify number of taps and cutoff frequency independently?

When specifying the properties of a moving average filter, is it possible to specify the number of taps and the cutoff frequency?

My guess is no since taps (the number of samples in a moving average filter) is what determines the cutoff frequency according to the frequency response equation.

If I'm wrong, how is it possible to specify the two?

• Are you asking if you can independently specify the number of taps and the frequency response of, specifically, a moving average filter? Or are you asking about the more general case of whether you have some freedom in the taps vs. cutoff frequency of a general FIR filter? – TimWescott Jan 2 at 0:37
• Yes, whether they can be specified independently. Eg can you say a moving average filter has a cut-off frequency of 100Hz and 5taps? My understanding is that one will affect the other so you can't specify both (unless they match by coincidence). – Eind997 Jan 2 at 7:19

For general FIR filters with $$N$$ taps you have $$N$$ degrees of freedom, so you can clearly choose the cut-off frequency independently of the number of taps. But this is not the case for a moving average filter.