Mean reduction of peak magnitudes in the FFR, due to the addition of a narrowband noise, at the QDT frequency (spectra of addition waveforms), the frequencies of the CDT, and the primary components (spectra of subtraction waveforms), averaged across conditions with the downward- and the upward-shifted complex. Complex tones were presented at 75 dB SPL. The 300-Hz wide noise had an rms level of 85 dB SPL and was centered on 290 and 310 Hz for the downward- and upward-shifted complex tones, respectively.