ears not covered
6.30 ears not covered. Listening situation where one or both ears are not covered with an earphone in a supra-aural cushion. Annotation An example of a situation where both ears are not covered would be for determining hearing threshold levels for acoustic stimuli. An example where only one ear is not covered would be for determining pure-tone bone-conduction hearing threshold levels when a bone vibrator is placed on the mastoid of one ear and an earphone is placed on the other ear for the purpose of masking. See C11.21 and 4.42.
critical band
6.24 critical band. (a) For loudness, that frequency band within which the loudness of a band of continuously distributed sound of constant sound pressure level is independent of its bandwidth (see also 6.31); (b) For masking (see C11.31), that frequency band of sound, being part of a continuous-spectrum noise covering a wide band, that contains sound power equal to that of a pure tone centered in the critical band and just audible in the presence of the wideband noise (see C11.32). Annotation 1 By “just audible” is meant audible in a specified fraction of the trials. Annotation 2 Use of the critical band to estimate masking should be limited to masking […]
aural combination tone
6.17 combination tone; aural combination tone. Secondary tone that can be perceived when two loud primary tones are presented simultaneously. The secondary tone may be a difference tone or a summation tone. Several combination tones may be produced from a single pair of primary tones. Unit, hertz (Hz). Annotation 1 Combination tones can also be produced by aural harmonics (see C11.38). Annotation 2 Combination tones are the result of the nonlinear characteristics of hearing.
combination tone
6.17 combination tone; aural combination tone. Secondary tone that can be perceived when two loud primary tones are presented simultaneously. The secondary tone may be a difference tone or a summation tone. Several combination tones may be produced from a single pair of primary tones. Unit, hertz (Hz). Annotation 1 Combination tones can also be produced by aural harmonics (see C11.38). Annotation 2 Combination tones are the result of the nonlinear characteristics of hearing.
click
6.16 click. Acoustic signal typically produced by exciting an earphone or speaker with a brief duration electrical pulse. Annotation 1 For an appropriately brief pulse (e.g., 0.1 ms), the acoustic spectrum of a click is primarily determined by the transfer function of the transducer. Annotation 2 Click stimuli are commonly used to obtain auditory brainstem responses and otoacoustic emissions. See 4.16 and C11.39.