Final Flashcards
(16 cards)
What does ANSI stand for?
American National Standards Institute
What is Attack Time?
the time required for hearing aid output to reach +/- 3 dB of its steady state level in response to an input step from 55 to 90 dB SPL
What is a coupler?
a device used to acoustically couple an earphone or hearing aid to a measurement microphone and to provide an acoustic load
What is Full on Gain (FOG)?
gain for 50 dB input SPL with the gain control set to max
What is Gain?
output sound pressure relative to input sound pressure, expressed in decibels
What is HA-1 Coupler used for?
ITE and ITC hearing aids
What is HA-2 Coupler used for?
BTE
What is Harmonic Distortion?
the addition of harmonic components to a signal
What is High Frequency Average (HFA)?
the average of value in dB at 1000, 1600 and 2500 Hz
What is Long-term Average Speech Spectrum (LTASS)?
the rms level of a speech passage in 1/3rd octave bands, averaged over the entire passage
What is OSPL90
output SL for 90 dB input SPL
the SPL developed in a 2 cc coupler when the input SPL is 90 dB, with the gain control of the hearing aids full-on
What is a probe microphone?
microphone having a sound inlet which is small enough to be acoustically unobtrusive when inserted into the ear canal
What is a reference microphone?
microphone used to measure the stimulus level in the measurement process to control it in the equalization process
What is release time?
the time required for hearing aid output to fall within +/- 4 dB of its steady state level for an input step from 90 to 55 dB SPL
What is reference test gain (RTG)?
the high frequency average gain for a 60 dB input SL with the gain control at reference test setting
What is reference test setting (RTS) of the gain control?
for a 60 dB input SPL, the setting of the gain control required to produce high frequency average gain within 1.5 dB of the
