PMID- 29495737
OWN - NLM
STAT- In-Data-Review
LR  - 20180302
IS  - 1520-8524 (Electronic)
IS  - 0001-4966 (Linking)
VI  - 143
IP  - 2
DP  - 2018 Feb
TI  - The area discontinuity between probe and ear canal as a source of
      power-reflectance measurement-location variability.
PG  - 1106
LID - 10.1121/1.5024360 [doi]
AB  - This study examined the effect of the area discontinuity between the
      measurement-probe sound source and ear canal on the plane-wave approximation of
      power reflectance. The area discontinuity was hypothesized to introduce
      measurement-location sensitivity to the power reflectance, especially above 5
      kHz. Measurements were made in human and artificial ear canals (tubes coupled to 
      an IEC711 ear simulator). In both cases, the power reflectance exhibited a
      high-frequency notch that decreased in frequency as the residual canal length
      increased. The area discontinuity between probe and canal was modeled as an
      inductance in series with the canal's acoustic impedance. To compensate for the
      effects of the discontinuity, the discontinuity's impedance was subtracted from
      the measured load impedance of the canal. In the artificial ears, compensation
      for the estimated area discontinuity removed the high-frequency notch and reduced
      the position dependence of the power reflectance. Subtracting the estimated
      discontinuity impedance from the load impedance in the human ears had a minimal
      effect on the power-reflectance measurement-location variability and magnitude of
      the high-frequency notch. The area-discontinuity between probe and ear canal is
      not supported as the primary source of measurement-variability in the plane-wave 
      approximation of the power reflectance in human ears.
FAU - Lewis, James D
AU  - Lewis JD
AD  - Department of Audiology and Speech Pathology, University of Tennessee Health
      Science Center, Knoxville, Tennessee 37996, USA.
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Acoust Soc Am
JT  - The Journal of the Acoustical Society of America
JID - 7503051
EDAT- 2018/03/03 06:00
MHDA- 2018/03/03 06:00
CRDT- 2018/03/03 06:00
PHST- 2018/03/03 06:00 [entrez]
PHST- 2018/03/03 06:00 [pubmed]
PHST- 2018/03/03 06:00 [medline]
AID - 10.1121/1.5024360 [doi]
PST - ppublish
SO  - J Acoust Soc Am. 2018 Feb;143(2):1106. doi: 10.1121/1.5024360.