automatic gain control

7.04  automatic gain control. Means (other than peak clipping) by which the gain is automatically controlled as a function of the level of the signal being amplified. Abbreviation,...

air pressure in an ear (or calibration cavity)

7.03  air pressure in an ear (or calibration cavity). Difference between the pressure of air within the external auditory canal (or in a calibration cavity) and atmospheric pressure at the location of the measurement. Unit, pascal (Pa). Annotation...

acoustic equivalent volume

7.02  acoustic equivalent volume. Alternate method of stating acoustic compliance. Acoustic equivalent volume Va may be expressed as:      Va =  γ po Ca =  ρo c2 Ca where γ is the ratio of...

acoustical coupler

7.01  acoustical coupler. Cavity of specified shape and volume used for the calibration of earphones or microphones in conjunction with a calibrated microphone adapted to measure the sound pressure developed in the cavity....

whistle register

6.94  whistle register. The highest phonational voice register. When producing pitches in this register, vibration occurs only in some anterior portion of the vocal folds. See also...