At uni professor was drawing inverse FFT of impulse response in a filter and he only used first few frequencies and then asked "can anybody see what's wrong with this chart?". We were all silent...
Turns out if you only use first few frequencies of FFT the filter output will look like it respond slightly before the signal arrives. It's a freaking time machine.
Turns out if you only use first few frequencies of FFT the filter output will look like it respond slightly before the signal arrives. It's a freaking time machine.