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I finally stumbled across an explanation for this.6) After test tones are done, go into Manual MCAAC--->EQ Professional------>Reverb View , and you can analyze the frequency response of individual channels at various frequencies. Based upon that data, you would select the appropriate capture delay time for MCAAC to capture data during for the upcoming EQ calibration.
Change that time frame under Manual MCAAC--->EQ Professional------>Advanced EQ Setup to whatever you decide is the appropriate capture delay time ....(Pioneer recommends 30-50 ms, but they encourage you to analyze the data under reverb view first and refer to the advanced MCAAc software manual for analysis purposes). Note: the default capture delay time is than 80-160 ms.
From Toole, The Measurement and Calibration of Sound Reproducing Systems
"Frequency Dependent Windowing (FDW) is the common theme of DSP software like Audiolense, Acourate, Dirac, Denis' DRC RePhase, and others. The idea is that the analysis and correction windows is long at low frequencies and sliding shorter as frequency increases: e.g. 750ms @ 20 Hz, 100ms @ 100Hz, 15ms at 1 kHz, and less than a millisecond @ 20 kHz. This more closely represents what we hear in small room acoustics. Acoustic and Psychoacoustic Issues in Room Correction by JJ Johnston explains why we hear what we hear in small room acoustics, hence why FDW.
So there is an element of the room at low frequencies, in addition to the speaker being equalized and as frequency increases the amount of room sound is windowed out to the point of just shaping the direct sound to match a target response for neutral, accurate sound reproduction."
Michael