HI all,
I have an (almost) full range 2-channel system (2 large passive floorstanders) that I have measured with an amplitude- and phase-calibrated microphone and corrected in two steps: first with REW's EQ, filter exported as wav and applied in convolver on original measured IR and then I fed the resulting EQd measurement to DRC-FIR by Denis Sbragion. The graph shows the resulting final FR (EQ+DRC) in blue, for one channel, pretty good. In dotted red is the unwrapped phase, in black excess phase and in grey minimum phase.
I am wondering why DRC has not reduced the excess phase? It is seemingly way off, a lot of phase rotation (thousands of degrees). In the graph there is zero IR delay, i.e. the impulse peak is at t=0.
In my second system (second graph with FR in green and phase in dotted blue, for one channel), with two active digital/dsp monitors and one active sub, I get the same phase pattern, sharp fall from sub bass to treble. Sub is time aligned. Again nice FR but is phase OK like this?
(never mind the absolut FR curve, it is without mic calibration)
(I did watch Amir's video where it is stated that deficiencies in absolute phase in loudspeaker audio reproduction is basically inaudible and what matters is channel symmetry and that phase changes smoothly with frequency, so maybe my question is not important? Or maybe my measurement result does not reflect reality when it comes to delay vs. frequency?)
I have an (almost) full range 2-channel system (2 large passive floorstanders) that I have measured with an amplitude- and phase-calibrated microphone and corrected in two steps: first with REW's EQ, filter exported as wav and applied in convolver on original measured IR and then I fed the resulting EQd measurement to DRC-FIR by Denis Sbragion. The graph shows the resulting final FR (EQ+DRC) in blue, for one channel, pretty good. In dotted red is the unwrapped phase, in black excess phase and in grey minimum phase.
I am wondering why DRC has not reduced the excess phase? It is seemingly way off, a lot of phase rotation (thousands of degrees). In the graph there is zero IR delay, i.e. the impulse peak is at t=0.
In my second system (second graph with FR in green and phase in dotted blue, for one channel), with two active digital/dsp monitors and one active sub, I get the same phase pattern, sharp fall from sub bass to treble. Sub is time aligned. Again nice FR but is phase OK like this?
(never mind the absolut FR curve, it is without mic calibration)
(I did watch Amir's video where it is stated that deficiencies in absolute phase in loudspeaker audio reproduction is basically inaudible and what matters is channel symmetry and that phase changes smoothly with frequency, so maybe my question is not important? Or maybe my measurement result does not reflect reality when it comes to delay vs. frequency?)
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