(This material was originally intended as part of the article “The Loudness War: Background, Speculation and Recommendations” [1] but was removed for reasons of scope and to keep that article to a manageable length.) In this paper, I briefly review a variety of metrics for quantifying the loudness and dynamic spread of audio recordings. This review was motivated by the need for objective ways o...

Buus and Florentine (ISP meeting 2001) presented evidence that basilar-membrane velocity growth functions are proportional to the square root of loudness functions derived from temporal and spectral integration. Although it is not possible to directly measure basilarmembrane activity in humans, it is likely that tone-burst otoacoustic emission input-output functions, at least at low and moderat...

This article describes a model of loudness for time-varying sounds that incorporates the concept of binaural inhibition, namely, that the signal applied to one ear can reduce the internal response to a signal at the other ear. For each ear, the model includes the following: a filter to allow for the effects of transfer of sound through the outer and middle ear; a short-term spectral analysis wi...

Whether a word was bawled, whispered, or yelped, captions will typically represent it in the same way. If they are your only way to access what is being said, subjective nuances expressed voice be lost. Since so much of communication carried by these nuances, we posit that if used as an accurate representation speech, embedding visual representations paralinguistic qualities into could help rea...

Loudness density is the distribution of loudness across dimensions of time and frequency. A computational model of loudness density is described that reproduces equal-loudness level contours from time-domain representations of tones. The model also demonstrates increase in loudness as the bandwidth of a multi-tone complex increases, an observation that is consistent with psychophysical measurem...

When predicting the overall loudness of time-varying sounds, it is necessary to use a function which calculates an overall value based on instantaneous loudness. Although N5 and LL(P) correlate for many sounds, their concepts are rather different. N5 is the loudness which is exceeded in five percent of the time, thus it is an ordinal value. LL(P) is the energetic mean of all instantaneous loudn...

Loudness change has been recently studied for tones with linearly varying levels. The published results by different authors revealed that direct ratings of loudness change for increasing sounds are higher compared to decreasing sounds. Interpretations of the results were different between Neuhoff’s (1998) and Teghtsoonian et al’s (2005) studies. The latter ones showed that judgments of loudnes...

Current loudness models and indicators of time-varying sounds such as the 95th percentile of the loudness distribution N5 all compute global loudness from short-term loudness time-series by leaving the temporal dimension out. Putting it differently, these models all rely on the assumption that the global loudness of a time-varying sound does not depend on the shape of its loudness pattern, i.e....

This article reviews the evolution of a series of models of loudness developed in Cambridge, UK. The first model, applicable to stationary sounds, was based on modifications of the model developed by Zwicker, including the introduction of a filter to allow for the effects of transfer of sound through the outer and middle ear prior to the calculation of an excitation pattern, and changes in the ...