A high frequency signal added to an audiotape in order to reduce distortions. The bias is recorded at a frequency above audibility. It takes on the distortion that would normally affect the desirable portion of the recording effectively moving the distortion up in frequency and out of the audible spectrum. The distortion is not eliminated but it is moved where it does not affect the recording. Bias must be carefully set so as to not adversely affect tape performance. If the bias extends too low, the desirable high frequency signals may be caught up in the bias and attenuated. Also, there is a level where the bias does no further good and distortion begins to re-enter the audible band requiring that bias be set very carefully.