warble tone
7.33 warble tone. Frequency-modulated sinusoid.
total harmonic distortion level
7.32 total harmonic distortion level. Ten times the logarithm to the base ten of the ratio of the sum of the squared amplitudes of the second and higher harmonic components of a signal to the square of the amplitude of the fundamental component. Abbreviation, THD. Annotation An alternative definition (IEC) is ten times the logarithm to the base ten of the ratio of the sum of the squared amplitudes of the second and higher harmonic components of a signal to the sum of the squares of the amplitude of the fundamental and higher harmonic components. For low THD values, the two methods yield similar results.
stationary noise
7.31 stationary noise. Noise signal with constant average statistical properties and negligibly small fluctuations of level within the period of observation.
nonstationary noise
7.30 nonstationary noise. Noise signal, with or without audible tones, for which the level and average statistical properties vary during the period of observation.
interaural cross correlation
7.29 cross correlation; interaural cross correlation. Covariance of signals vs. time shift; i.e., the degree of similarity of a reference signal and a time-shifted signal, as a function of time shift or delay. Annotation 1 The cross correlation is calculated as where T is the observation period, and a(t) and b(t) are the respective signals. Annotation 2 The coefficient of correlation varies from +1 (perfectly correlated; i.e., the two signals are identical), through zero (completely uncorrelated; i.e., the two signals are completely independent or orthogonal), to –1 (perfectly correlated, but with a complete 180° phase inversion between the signals). Annotation 3 Auto correlation is the degree of similarity of a […]