Source: https://jmrplens.github.io/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/ Stationary loudness per ISO 532-2:2017 (Moore-Glasberg method). Clean-room implementation of the spectral loudness model of ISO 532-2:2017, the third calculation method of the ISO 532 series (distinct from the Zwicker method of ISO 532-1 and the Sottek model of ECMA-418-2). The procedure of Clause 7 (Figure 1) transforms a stationary sound spectrum into a loudness value through five stages: * the fixed outer-ear and middle-ear transfer functions that map the recorded spectrum to the spectrum at the cochlea (clauses 7.2, 7.3, Table 1); * the level-dependent rounded-exponential (roex) auditory filter bank that turns that spectrum into an excitation pattern along the ERB-number scale (clause 7.4, Formulae 1-6), sampled at ERB-number `i` from 1.8 Cam to 38.9 Cam in 0.1 Cam steps; * the compressive transformation of excitation into specific loudness `N'(i)` in sone/Cam (clause 7.5, Formulae 7-9, Tables 2-4); * the binaural inhibition model that combines the two ears (clause 8.1, Formulae 10-13); and * the integration of specific loudness over the ERB-number scale to the total loudness `N` in sone, with the loudness level `L_N` in phon obtained by inverting the loudness/loudness-level relationship of Table 5 (clause 8.2). The specific-loudness calibration constant `C` of Formula (7) is the value tabulated by the standard (0.0617 sone/Cam); a 1 kHz tone at 40 dB SPL presented binaurally in a free field yields 1.000 sone by definition of the sone (clause 3.17), which this implementation reproduces without tuning. The stationary method is spectrum based. [`loudness_moore_glasberg_from_spectrum`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#loudness_moore_glasberg_from_spectrum) takes the exact sinusoidal-component representation of clauses 5.2/5.4, [`loudness_moore_glasberg_from_third_octave`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#loudness_moore_glasberg_from_third_octave) takes the 29 one-third-octave band levels of clause 5.5, and [`loudness_moore_glasberg`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#loudness_moore_glasberg) forms the narrowband (FFT) line spectrum of a calibrated pressure signal and feeds it to the exact sinusoidal-component method. > Auto-generated from the source docstrings by `scripts/generate_api_docs.py` (`make api-docs`). Do not edit by hand. ## loudness_moore_glasberg ```python loudness_moore_glasberg( x: list[float] | np.ndarray, fs: float, *, field: Literal['free', 'diffuse', 'eardrum'] = 'free', presentation: Literal['binaural', 'diotic', 'monaural'] = 'binaural', ) -> MooreGlasbergLoudness ``` Moore-Glasberg loudness of a calibrated stationary pressure signal. Convenience wrapper around [`loudness_moore_glasberg_from_spectrum`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#loudness_moore_glasberg_from_spectrum): the signal's narrowband (FFT) line spectrum is formed and each bin is passed to the exact sinusoidal-component method of ISO 532-2:2017 (clauses 5.2/5.4). Because the model computes the excitation pattern per spectral component (Formula 5), a pure tone enters as a single line - so a calibrated 1 kHz tone at 40 dB SPL yields 1.000 sone / 40 phon (the definitional anchor), matching [`loudness_moore_glasberg_from_spectrum`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#loudness_moore_glasberg_from_spectrum). The signal must be calibrated so that `x` is the instantaneous sound pressure in pascals. **Parameters** | Name | Description | | :--- | :--- | | `x` | Single-channel calibrated pressure signal in pascals. | | `fs` | Sampling rate in Hz (positive). | | `field` | `"free"` (default), `"diffuse"` or `"eardrum"`. | | `presentation` | `"binaural"` (default; alias `"diotic"`) or `"monaural"`. | **Returns:** A [`MooreGlasbergLoudness`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#mooreglasbergloudness). ## loudness_moore_glasberg_from_spectrum ```python loudness_moore_glasberg_from_spectrum( components: Sequence[tuple[float, float]] | np.ndarray, *, field: Literal['free', 'diffuse', 'eardrum'] = 'free', presentation: Literal['binaural', 'diotic', 'monaural'] = 'binaural', ) -> MooreGlasbergLoudness ``` Moore-Glasberg loudness from a sinusoidal-component spectrum. Implements the exact spectral input of ISO 532-2:2017 clauses 5.2/5.4: the sound is specified as a set of discrete sinusoidal components, each a `(frequency_Hz, level_dB_SPL)` pair (levels re 20 uPa in the stated sound field). Bands of noise can be represented by the equivalent set of closely spaced components of clause 5.3. **Parameters** | Name | Description | | :--- | :--- | | `components` | Sequence of `(frequency_Hz, level_dB)` pairs (or an `(n, 2)` array). An empty spectrum yields zero loudness. | | `field` | Listening condition setting the outer-ear transfer: `"free"` (frontal free field, default), `"diffuse"` (diffuse field) or `"eardrum"` (levels already specified at the tympanic membrane, e.g. a flat earphone). | | `presentation` | `"binaural"` (default; `"diotic"` is an equivalent alias: the same sound at both ears) or `"monaural"` (one ear only). | **Returns:** A [`MooreGlasbergLoudness`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#mooreglasbergloudness). A 1 kHz tone at 40 dB SPL in a free field presented binaurally yields 1.000 sone / 40 phon by definition of the sone. ## loudness_moore_glasberg_from_third_octave ```python loudness_moore_glasberg_from_third_octave( band_levels: Sequence[float] | np.ndarray, *, field: Literal['free', 'diffuse', 'eardrum'] = 'free', presentation: Literal['binaural', 'diotic', 'monaural'] = 'binaural', ) -> MooreGlasbergLoudness ``` Moore-Glasberg loudness from 29 one-third-octave band levels. Implements the practical spectral input of ISO 532-2:2017 clause 5.5: the sound is specified by the sound pressure levels in the 29 adjacent one-third-octave bands with nominal centre frequencies 25 Hz to 16 kHz (IEC 61260-1). Each band is expanded into the equivalent set of sinusoidal components and the exact method is applied. **Parameters** | Name | Description | | :--- | :--- | | `band_levels` | 29 band levels in dB SPL (re 20 uPa), 25 Hz..16 kHz. | | `field` | `"free"` (default), `"diffuse"` or `"eardrum"`. | | `presentation` | `"binaural"` (default; alias `"diotic"`) or `"monaural"`. | **Returns:** A [`MooreGlasbergLoudness`](/phonometry/reference/api/psychoacoustics/loudness-moore-glasberg/#mooreglasbergloudness). ## MooreGlasbergLoudness ```python MooreGlasbergLoudness( loudness: float, loudness_level: float, specific: np.ndarray, erb_number: np.ndarray, centre_frequencies: np.ndarray, field: str, presentation: str, ) ``` Result of an ISO 532-2:2017 Moore-Glasberg loudness calculation. `loudness` is the total loudness N in sone; `loudness_level` is the loudness level L_N in phon (obtained by inverting the loudness/loudness- level relationship of Table 5). `specific` holds the specific loudness N'(i) in sone/Cam sampled at the ERB-number grid `erb_number` (Cam), i.e. i from 1.8 Cam to 38.9 Cam in 0.1 Cam steps (372 values), and `centre_frequencies` the corresponding auditory-filter centre frequencies in Hz. For a binaural (diotic) result the specific-loudness pattern is that of a single ear before binaural inhibition; the total `loudness` already includes the binaural summation. `field` and `presentation` echo the listening conditions. ### MooreGlasbergLoudness.plot() ```python MooreGlasbergLoudness.plot( ax: Axes | None = None, *, language: str = 'en', **kwargs: Any, ) -> Axes ``` Plot the specific loudness N'(i) over the ERB-number scale. Requires matplotlib (`pip install phonometry[plot]`); returns the `Axes`. See `._plotting`.