Here it is the difference equation we have:
y(n) = -0.25x(n) - 0.15x(n − 1) + 0.78x(n − 2) − 0.15x(n − 3) - 0.25x(n - 4)
I understand that is FIR. The coefficients are selected in the way that certain input signal frequencies are removed by such convolution system. Take Matlab audio file gong.mat for example, we read the file then we have input signal x and sampling rate Fs, then through such system, we have output signal y. How do we understand the filter coefficients that make some input signal frequencies are filtered? Different coefficients lead to different filter type? Can we estimate what frequencies are removed?