Accuracy and simplicity of analytical expressions for the relations between frequency and critical bandwidth as well as critical-band rate (in Bark) are assessed for the purpose of applications in speech perception research and in speech technology. The equivalent rectangular bandwidth (ERB) is seen as a measure of frequency resolution, while the classical critical-band rate is considered a measure of tonotopic position. For the conversion of frequency to critical-band rate, and vice versa, the inversible formula z = [26.81/(1 + 1960/ f) ]-0.53 is proposed. Within the frequency range of the perceptually essential vowel formants (0.2-6.7 kHz), it agrees to within _+ 0.05 Bark with the Bark scale, originally published in the form of a table.

The acoustic effects of the adjustment in vocal effort that is required when the distance between speaker and addressee is varied over a large range (0.3-187.5 m) were investigated in phonated and, at shorter distances, also in whispered speech. Several characteristics were studied in the same sentence produced by men, women, and 7-year-old boys and girls: duration of vowels and consonants, pausing and occurrence of creaky voice, mean and range of F0, certain formant frequencies (F1 in [a] and F3), sound-pressure level (SPL) of voiced segments and [s], and spectral emphasis. In addition to levels and emphasis, vowel duration, F0, and F1 were substantially affected. "Vocal effort" was defined as the communication distance estimated by a group of listeners for each utterance. Most of the observed effects correlated better with this measure than with the actual distance, since some additional factors affected the speakers' choice. Differences between speaker groups emerged in segment durations, pausing behavior, and in the extent to which the SPL of [s] was affected. The whispered versions are compared with the phonated versions produced by the same speakers at the same distance. Several effects of whispering are found to be similar to those of increasing vocal effort.

The role of intrinsic factors determining perceived degree of vowel openness was examined. In order to determine the role of F1 and F0, one-formant vowels, covering a wide range of fundamental and formant frequencies, were identified by 23 subjects who were native speakers of a Bavarian dialect in which five degrees of openness occur distinctively. The significance of intrinsic factors other than F1 and F0 was also studied using synthetic versions of natural vowels with F1 and/or F0 systematically displaced in frequency. It was found that, generally, the tonality distance between F1 and F0 is decisive for openness, while the higher formants contribute marginally. It was further found that the distance between widely spaced formants, as between F2 and F1 in front vowels, is not crucial for vowel identification. The results are evaluated in terms of a psychoacoustic model of identification by pattern matching. the model incorporates two basic assumptions. First, a certain pattern of excitation along the basilar membrane is recognized as a given feature regardless of position along the membrane. Second, there is an integration band with a width of 3 Bark effective in spectrum envelope recognition.

Speech signals contain various types of information that can be grouped under the headings phonetic, affective, personal and transmittal. Listeners are capable of distinguishing these. Previous theories of speech perception have not considered this fully. They have mainly been concerned with problems relating exclusively to phonetic quality. The theory presented in this paper considers speech signals as the result of allowing conventional gestures to modulate a carrier signal that has the personal characteristics of the speaker, which implies that in general the conventional information can only be retrieved by demodulation.

It is shown that within-speaker variations in vocal effort and phonation affect fundamental frequency (F₀) and the formant frequencies of vowels in the sense of a linear compression/expansion of the spectral separations between them, given an adequate scaling of pitch. Between-speaker variations in size correspond to a translation of the spectral peaks shaped by F₀ and the formants if pitch is scaled tonotopically (in Bark). On the basis of these observations, invariant cues to vowel quality are suggested. It is further shown that vowels produced by adult women tend to be phonetically more explicit and, hence, more peripheral in ‘vowel space’ than those of men and children. It is also shown that the formant frequencies of vowels subjected to paralinguistic variation are related by power functions of frequency.

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Early physical cosmologies were based on interpretations of the cosmic redshift for which there was insufficient evidence and on theories of gravitation that appear to be falsified by galactic dynamics. Eventually, the big bang paradigm came to be guarded against refutation by ad hoc hypotheses (dark matter, cosmic inflation, dark energy) and free parameters. Presently available data allow a more satisfactory phenomenological approach. Using data on magnitude and redshift from 892 type Ia supernovae, it is first shown that these suggest that the redshift factor (1 + z) is simply an exponential function of distance and that, for "standard candles", magnitude m = 5 log[(1 + z) ln(1 + z)] + const. While these functions are incompatible with a big bang, they characterize certain tired light models as well as exponential expansion models. However, the former are falsified by the stretched light curves of distant supernovae and the latter by the absence of a predicted 1+z increase in the angular sizes of galaxies. Instead, the observations suggest that physical processes speed up and objects contract uniformly as an exponential function of time, standards of measurement not excluded, and only free waves being excepted. Distant events proceed, then, more slowly, while angular sizes remain unaffected, approximately as observed. Since all objects contract in proportion, the Universe retains a static appearance. A corresponding physical theory, which should also explain galactic dynamics, remains yet to be derived from first principles. A way to do this, satisfying also Mach"s principle, is vaguely suggested.