A method for experimental estimation of SEA loss factors based on CMTF:s (complex modulation transfer functions), has been earlier reported. In the method the low frequency part of the CMTF curve is fitted to a SEA model. The used SEA model has minimum-phase transfer functions. The CMTF curve, however, is not minimum-phase due to a propagation delay. To yield better SEA parameter estimations, the delay should be estimated and removed by shifting the origin of the squared impulse response. Alternatively, using the Hilbert transform, the minimum-phase version of the CMTF can be computed from its magnitude function. The SEA loss factors are estimated for the non-modified, the time-shifted and the Hilbert manipulated response. In the fit procedure the CMTF curve up to the "knee" has been used, rather arbitrary. The damping can be found in the very low frequency part of the CMTF curve, which is obvious from the moment theorem. It means that the centre of gravity time of the squared impulse response is equal to minus the slope of the phase function of CMTF at zero frequency. The centre of gravity time, the slope of the phase function and the decay constant from decay rates of the reverberation curve are computed.
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