TY - JOUR
T1 - Mechanism for bandpass frequency characteristic in distortion product otoacoustic emission generation
AU - Fahey, P. F.
AU - Stagner, B. B.
AU - Martin, G. K.
N1 - Funding Information:
This research was supported in part by funds from the Public Health Service [supported in part by the Public Health Service (DC000613, DC003114) and the Research Fund of the Department of Otolaryngology, University of Colorado Health Sciences Center, Denver CO] and DOE (PFF). We thank two anonymous reviewers for many useful comments and suggestions.
PY - 2006/2
Y1 - 2006/2
N2 - It is commonly observed that the levels of the 2f1-f2 and the other mf1-nf2 (m=n+1=integer) distortion product otoacoustic emissions (DPOAEs) initially increase in level for fixed f 2 as f1 →f2, starting at f1 ≪ f2, and then begin to decrease. When these DPOAE levels are plotted as a function of either the distortion product frequency (f dp) or f2/f1 the curve has an approximate bandpass shape. It has been hypothesized that this effect is due to (1) a second filter, (2) suppression of distortion generation by the primary tones, (3) reemission of distortion products from the distortion product place (on the basilar membrane), (4) the presence of an even order nonlinearity, and (5) cancellation of the DPOAE due to the vector addition of multiple sources of distortion product. In this study distortion products were produced with f 1 sweep conditions where there would be minimal vector cancellation of multiple DPOAE sources. It was observed that under this condition, there is no or minimal bandpass shape of the DPOAE generation curve. Therefore, the data support the hypothesis that the bandpass shape obtained with traditional f 1 sweeps is due to vector cancellation from multiple sources.
AB - It is commonly observed that the levels of the 2f1-f2 and the other mf1-nf2 (m=n+1=integer) distortion product otoacoustic emissions (DPOAEs) initially increase in level for fixed f 2 as f1 →f2, starting at f1 ≪ f2, and then begin to decrease. When these DPOAE levels are plotted as a function of either the distortion product frequency (f dp) or f2/f1 the curve has an approximate bandpass shape. It has been hypothesized that this effect is due to (1) a second filter, (2) suppression of distortion generation by the primary tones, (3) reemission of distortion products from the distortion product place (on the basilar membrane), (4) the presence of an even order nonlinearity, and (5) cancellation of the DPOAE due to the vector addition of multiple sources of distortion product. In this study distortion products were produced with f 1 sweep conditions where there would be minimal vector cancellation of multiple DPOAE sources. It was observed that under this condition, there is no or minimal bandpass shape of the DPOAE generation curve. Therefore, the data support the hypothesis that the bandpass shape obtained with traditional f 1 sweeps is due to vector cancellation from multiple sources.
UR - https://www.scopus.com/pages/publications/31744442917
UR - https://www.scopus.com/pages/publications/31744442917#tab=citedBy
U2 - 10.1121/1.2146088
DO - 10.1121/1.2146088
M3 - Article
C2 - 16521760
SN - 0001-4966
VL - 119
SP - 991
EP - 996
JO - Journal of the Acoustical Society of America
JF - Journal of the Acoustical Society of America
IS - 2
ER -