This study analyzed the range of (alpha) waves (8--13 Hz) of continuous brain waves (CBW) and compared them with the scale value of the subjective preference of the sound field in a change of the interaural cross-correlation function (IACC) [Ando, Concert Hall Acoustics (Springer-Verlag, Heidelberg, 1985)]. The source signal was Sinfonietta, Opus 48; third movement, composed by Arnold. The scale value of the subjective preference and the CBWs to a paired stimuli, i.e., reference stimuli (IACC=1.0) and test stimuli (IACC=0.3 or 0.65), which were presented alternatively were compared. It is found that the value of the effective duration ((tau)[inf e]) of the autocorrelation function (ACF) of the (alpha) waves from only the right hemisphere corresponds well to the subjective preference. It is considered, therefore, that (tau)[inf e] is an objective measure reflecting the subjective preference [Chen and Ando (unpublished)].