“…Not only is low-frequency noise much greater than high-frequency noise, it is also much greater than the actual low-frequency OAE signals. Therefore, low-frequency OAEs are almost always concealed by acoustic background noise in a typical recording under clinical settings (Andersson, Arlinger, & Jacobsson, 2000;Hussain, Gorga, Neely, Keefe, & Peters, 1998 Due to this acoustic background noise limitation, the performance of OAE measurements suffers greatly when assessing low-frequency cochlear functions such as at 500 Hz in clinics (Gorga et al, 1993;Harrison & Norton, 1999;Suckfull et al, 1996). Consequently, the lowest frequency for measuring specific OAE frequencies, such as in DPOAEs, is typically set by manufacturers at 1000 Hz for f 2 primary tones.…”