Wow, I had never thought that the "linear phase" filters used as CD brickwall filters are so called because they have no phase distortion! All frequencies are delayed equally. This requires an acausal filter to realize (which could be an analog system with delay lines).
The price paid for this magic of linear phase is the pre-ringing artifacts. The pre-ringing is at ultrasonic frequencies and typically quite small.
Reverting to causal minimum phase filters get you no pre-ringing, but the post ringing is far larger, and the pulse itself is distorted because of phase shift before the cutoff point. (Just one example is shown. The phase distortion and post ringing can be played against each other in different ways.)
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