FIG. 8.

The upper panel shows the bias level (dB SPL) that produced maximum SFOAE sidebands as a function of probe frequency. Vertical error bars are the width of the sideband versus bias level curves (e.g., Fig. 2) measured 0.5 dB down from the maximum. Data obtained with a 150 Hz bias tone are in gray (nine ears from eight guinea pigs) while data obtained with either a 50 Hz or 70 Hz bias tone are in black (five ears from five different guinea pigs). Different symbols represent different guinea pig ears. Lines connect data collected from a given ear. The lower panel shows the low-frequency bias tone level (dB SPL) needed to achieve 50% CAP suppression as a function of frequency. Vertical error bars are estimates of 40% and 60% CAP suppression. Unlike the cat data, guinea pig data do not show a systematic trend with frequency.