Small caliber guns have higher magnitude at higher frequencies and larger caliber guns have higher magnitude at lower frequencies. is this true ? because I am not see this in my test: that is the fft of a 9MM gun, As one can see there are low magnitudes at low frequencies and higher magnitudes at higher frequencies. Also the peck frequencies are around 807 Hz. A 9MM handgun is a Small caliber gun. that is an fft of a larger caliber gun and the magnitudes are higher at high frequencies ... am I missing something ?