The Phase Matters

It seems usually admitted that the human hearing isn't sensible to the phase relation between frequencies. But since this phase relation also modifies the waveform, an attentive listening may detect variations. I've added allpass filters to create a phase shift at 400 Hz per 90° increments.
You can hear how reverberations and transients are affected by the phase shifting. The first 90° is obvious on the reverb, the stereo placement of the guitare and percussions. The following loops are differently affected by the phase variations. The guitar tone amost doesn't change while the percussions may vary.

Note also that a limiter inserted after an allpass filter or more will have a different behaviour because of the peak value modifications. In this demo the maximal peak values may change from -2.32 dB to +3.81 dB. Which is not a detail for human hearing nor for any downstream processor.

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