API Reference

The complete public API, one page per module. Import the domain subpackage and call through it:

Auto-generated from the source docstrings by scripts/generate_api_docs.py (make api-docs). Do not edit by hand.

Every documented name can also be imported directly from the top-level package (from phonometry import leq).

Module	Summary
phonometry	Package-level names defined in phonometry/__init__.py itself.
filters.core	Core processing logic and FilterBank class for phonometry.
filters.weighting	Weighting filters (A, B, C, D, G, AU, 468, Z), time weighting utilities and the Linkwitz-Riley crossover.
filters.equalizer	Parametric equalizer biquads per the RBJ Audio EQ Cookbook.
filters.frequencies	Frequency calculation logic according to ANSI/IEC standards.
filters.compliance	IEC 61260-1:2014 band-filter class verification.
filters.time_invariance	The exponential-sweep test of a band filter: time-invariant operation.
filters.periodic_tests	Periodic tests of band filters (IEC 61260-3:2016): test frequencies and verdict.
filters.weighting_compliance	IEC 61672-1:2013 frequency-weighting class verification.

Module	Summary
signals.levels	Integrated and statistical sound levels (Leq, LAeq, LN percentiles).
signals.spectra	Calibrated spectral-density estimation with statistical error analysis.
signals.multitaper	Thomson multitaper spectral estimation (Percival & Walden 1993, Ch. 7).
signals.windows	Figures of merit of a spectral-analysis taper (Harris 1978).
signals.miso	Multiple and partial coherence of a multiple-input/single-output system.
signals.time_frequency	Calibrated time-frequency analysis: STFT spectrogram and zoom FFT.
signals.test_signals	Test signals and sample-rate utilities.
signals.phase	Phase utilities: minimum phase, group delay and excess phase.
signals.cepstrum	Cepstral analysis: real/power/complex cepstrum, liftering and echo detection.
signals.synchronous_average	Time synchronous averaging (TSA) of a periodic waveform in noise.
signals.inversion	Regularized spectral inversion with frequency-dependent regularization.
signals.correlation	Correlation analysis and time-delay estimation.
signals.envelope	Envelope and instantaneous phase via the Hilbert transform.

Module	Summary
metrology.calibration	Calibration utilities for mapping digital signals to physical SPL levels.
metrology.sound_calibrator	Sound calibrators (IEC 60942:2017): the class tables and the verdict on one.
metrology.conformance	The conformance rule of IEC TC 29: a deviation, its limits and its uncertainty.
metrology.uncertainty	Measurement uncertainty by the GUM and its Monte Carlo supplement.
metrology.data_qualification	Random-data qualification: stationarity tests and Rice crossing statistics.
metrology.reference_values	Preferred reference values for acoustical and vibratory levels (ISO 1683:2015).
metrology.random_incidence	Random-incidence and diffuse-field sensitivity of a sound level meter (IEC 61183:1994).
metrology.free_field_corrections	Corrections that bring a sound level meter to its free-field response (IEC 62585:2012).
metrology.sound_level_meter	Periodic tests of a sound level meter (IEC 61672-3:2013): the verdict.
metrology.comparison_calibration	Calibration of a measurement microphone by comparison with a reference microphone (IEC 61094-5:2016, pressure; IEC 61094-8:2012, free field).
metrology.reciprocity_calibration	Primary calibration of laboratory standard microphones by reciprocity: the sensitivities that come out of three pair measurements, and the uncertainty budget that goes with them (IEC 61094-2:2009 clause 5.7 and clause 7, IEC 61094-3:2016 clause 5.7 and clause 7).
metrology.reciprocity_coupler	Pressure calibration of laboratory standard microphones by reciprocity in a closed coupler (IEC 61094-2:2009).
metrology.reciprocity_free_field	Free-field calibration of laboratory standard microphones by reciprocity (IEC 61094-3:2016 with its corrigendum IEC 61094-3:2016/COR1:2016).

Module	Summary
fluids	fluids domain of phonometry (see module docstrings).
fluids.air	Humid air (IEC 61094-2:2009, Annex F).
fluids.gas	An ideal gas from the two numbers a gas table prints.
fluids.water	Sea water: its speed of sound, and its density.
fluids.catalogue	Fluid states read from a printed page.
fluids.nonlinearity	The nonlinearity parameter B/A of liquids, as a handbook tabulates it.

Module	Summary
solids.elastic	Three longitudinal wave speeds of a solid, and which one a table prints.
solids.catalogue	Solid materials as one published table prints them.
solids.damping	Commercial damping materials, with the temperature and the frequency.
solids.damping_treatments	Damping treatments rated by the decay rate of a treated panel.
solids.nonlinearity	The nonlinearity parameter of solids, as a handbook tabulates it.
solids.orthotropic_wood	Wood, which is not the same material in two directions.
solids.plateau	The three numbers a panel needs before its transmission loss can be sketched.

Module	Summary
io	Files: measurement audio, its calibration sidecar and catalogues of materials.

Module	Summary
psychoacoustics.loudness.zwicker	Zwicker loudness for stationary and time-varying sounds per ISO 532-1:2017.
psychoacoustics.loudness.moore_glasberg	Stationary loudness per ISO 532-2:2017 (Moore-Glasberg method).
psychoacoustics.loudness.moore_glasberg_time	Time-varying loudness per ISO 532-3:2023 (Moore-Glasberg-Schlittenlacher).
psychoacoustics.loudness.ecma	Psychoacoustic loudness per ECMA-418-2:2025 (4th ed., Sottek Hearing Model).
psychoacoustics.loudness.contours	Normal equal-loudness-level contours per ISO 226:2023.
psychoacoustics.quality.sharpness	Sharpness per DIN 45692:2009-08.
psychoacoustics.quality.roughness_ecma	Psychoacoustic roughness per ECMA-418-2:2025 (4th ed., Sottek Hearing Model).
psychoacoustics.quality.tonality	Prominent discrete tone assessment per ECMA-418-1:2024 (3rd edition).
psychoacoustics.quality.tonality_ecma	Psychoacoustic tonality per ECMA-418-2:2025 (4th ed., Sottek Hearing Model).
psychoacoustics.quality.tone_audibility	Objective audibility of tones in noise — engineering method (ISO/PAS 20065:2016).
psychoacoustics.quality.fluctuation_strength	Fluctuation strength after Fastl & Zwicker / Osses et al.
psychoacoustics.quality.fluctuation_strength_ecma	Psychoacoustic fluctuation strength per ECMA-418-2:2025 (4th ed., Clause 9).
psychoacoustics.quality.annoyance	Psychoacoustic annoyance (PA) after Fastl & Zwicker.
psychoacoustics.erb_scale	The ERB_N scale: auditory-filter bandwidth and the Cam frequency scale.

Module	Summary
speech.sti	Speech Transmission Index (STI) per IEC 60268-16:2020 (Edition 5).
speech.sii	Speech Intelligibility Index (SII) per ANSI S3.5-1997 (R2017).
speech.objective_intelligibility	Short-Time Objective Intelligibility (STOI and ESTOI).

Module	Summary
hearing.threshold	Age-related hearing threshold (ISO 7029:2017) and audiometric reference zero (ISO 389-7:2005).
hearing.audiometry	Pure-tone audiometry: the test room, the threshold rules and their uncertainty (ISO 8253-1:2010).
hearing.sound_field_audiometry	The sound field of an audiometric test room (ISO 8253-2:2009).
hearing.noise_induced_hearing_loss	Estimation of noise-induced hearing loss (ISO 1999:2013).
hearing.occupational_exposure	Occupational noise exposure: measurement strategies and uncertainty (ISO 9612:2009).
hearing.real_ear_attenuation	Real-ear attenuation of a hearing protector and its uncertainty (ISO 4869-1:2018).
hearing.hearing_protectors	What a hearing protector leaves at the ear (ISO 4869-2:2018).
hearing.active_noise_reduction	Total attenuation of an active noise reduction earmuff (ISO 4869-6:2019).
hearing.earmuff_insertion_loss	The insertion loss of an earmuff on an acoustic test fixture (ISO 4869-3:2007).

Module	Summary
room.acoustics	Room acoustic parameters from impulse responses per ISO 3382-1:2009 (performance spaces) and ISO 3382-2:2008 (ordinary rooms).
room.auditorium	Auditorium measures derived from impulse responses (ISO 3382-1:2009, Annex A).
room.impulse_response	Impulse-response acquisition per BS EN ISO 18233:2006.
room.noise_criteria	Room-noise rating curves per ANSI/ASA S12.2-2019.
room.open_plan	Open-plan-office spatial metrics per ISO 3382-3:2012.
room.reverberation_prediction	Reverberation-time prediction from room geometry and absorption.
room.enclosed_space_absorption	Sound absorption in enclosed spaces (EN 12354-6:2003).
room.image_source	Synthetic room impulse response by the image-source method (rectangular room).
room.steady_field	Steady-state sound field in a room: room constant, critical distance, level.
room.modes	Normal modes of a rectangular room: frequencies, kinds, count and density.
room.crowd_noise	Crowd self-noise in a restaurant: the cocktail-party equilibrium.
room.spatial_decay	Spatial sound distribution curves in workrooms (ISO 14257:2001).
room.workroom_prediction	Predicting sound propagation in a workroom (ISO 11690-3:1998).

Module	Summary
building.measurement.insulation	Field measurement of sound insulation: airborne (ISO 16283-1:2014), impact (ISO 16283-2:2020) and facade (ISO 16283-3:2016).
building.measurement.low_frequency	Low-frequency procedure of ISO 16283, shared by all three parts.
building.measurement.ratings	Single-number weighted ratings of sound insulation and their spectrum adaptation terms (ISO 717-1 airborne, ISO 717-2 impact).
building.catalogue	Transmission loss as the books print it, one row per construction.
building.impact_catalogue	Impact insulation as a handbook prints it, one row per floor-ceiling.
building.datasheets	Sound insulation as a data sheet or a test report prints it.
building.prediction.panel_transmission	Predicted airborne sound reduction index of panels (Bies, Hansen & Howard 2017, Engineering Noise Control 5e, Section 7.2; Sharp 1973).
building.prediction.masonry_cavity_wall	Wall ties in masonry cavity walls: the structural bridge across the cavity (Hopkins 2007, Sections 3.11.3.2 and 4.3.5.4.1).
building.measurement.heavy_impact	Heavy and soft impact sources: rubber ball and bang machine (ISO 16283-2:2020 Annex A, ISO 10140-5:2021 Annex F, JIS A 1418-2:2019, ISO 717-2:2020 Annex D).
building.prediction.ceiling_plenum	Suspended-ceiling plenum flanking path (Vigran 9.2.3 after Mechel 1980; ISO 140-9 / ISO 10848-2; ASTM E1414 / ASTM E413).
building.prediction.aperture_transmission	Sound transmission through slits, holes and apertures (Hopkins 2007, Sound Insulation, Section 4.3.10; Gomperts 1964; Wilson & Soroka 1965).
building.measurement.lab_insulation	Laboratory sound insulation of building elements (ISO 10140).
building.measurement.lab_improvement	Improvement of sound insulation measured in the laboratory: a lining on a basic element and a floor covering on a reference floor (ISO 10140-1:2021 Annexes G and H).
building.measurement.joint_insulation	Sound reduction index of joints filled with fillers or seals (ISO 10140-1:2021 Annex J).
building.measurement.rainfall_sound	Sound of rain on roofs, roof windows and rooflights, measured in the laboratory with artificial rain (ISO 10140-1:2021 Annex K, ISO 10140-5:2021 Annexes H and I).
building.measurement.survey_insulation	Field survey method for sound insulation and service-equipment noise (ISO 10052:2021).
building.measurement.service_equipment	Sound from service equipment and activities in buildings, engineering method.
building.measurement.intensity_insulation	Sound insulation measured with sound intensity (ISO 15186).
building.measurement.flanking_transmission	Laboratory measurement of flanking sound transmission (ISO 10848:2006/2010).
building.prediction.facade	Façade sound insulation and outdoor radiation prediction (EN 12354-3/-4:2000).
building.prediction.simplified_model	Building acoustic performance prediction (EN 12354-1/-2:2000).
building.prediction.detailed_model	Detailed per-band building prediction (EN/ISO 12354-1/-2:2017).
building.measurement.uncertainty	Measurement uncertainty in building acoustics (ISO 12999-1:2020).
building.measurement.floor_covering_improvement	Impact-sound improvement of floor coverings on a small mock-up (ISO 16251-1:2014).
building.prediction.resilient_layers	Prediction of resilient-layer performance: tapping force, floor coverings, floating floors.
building.prediction.linings	Prediction of wall and ceiling linings: the weighted improvement an additional layer gives the element behind it (ISO 12354-1:2017 Annex D).
building.measurement.structure_borne_power	Structure-borne sound power of building equipment (EN 15657:2018; ISO 9611).
building.prediction.installed_structure_borne	Installed structure-borne sound from service equipment (EN 12354-5:2009).
building.regulation.spain	Spanish building code CTE DB-HR: global indices and requirement checks.

Module	Summary
materials.absorbers.sound_absorption	Sound absorption in a reverberation room: BS EN ISO 354:2003.
materials.absorbers.rating	Single-number rating of sound absorption (ISO 11654:1997).
materials.absorbers.uncertainty	Measurement uncertainty for sound absorption (ISO 12999-2:2020).
materials.absorbers.airflow_resistance	Airflow resistance of porous materials: ISO 9053-1 and ISO 9053-2.
materials.resilient.dynamic_stiffness	Dynamic stiffness of resilient materials under floating floors (EN 29052-1:1992).
materials.resilient.moduli	The dynamic modulus of resilient materials, as a textbook tabulates it.
materials.absorbers.impedance_tube	Two-microphone transfer-function method in the impedance tube.
materials.absorbers.four_microphone	Four-microphone transfer-matrix method for the transmission of a specimen.
materials.absorbers.standing_wave	Standing-wave-ratio method for normal-incidence absorption and impedance.
materials.absorbers.porous	Porous-material models and resonant sheet impedances.
materials.absorbers.catalogue	Porous specimens as the pages that print them have them.
materials.absorbers.resistive_sheets	Thin resistive facings, and the resistance of one square metre of them.
materials.absorbers.measured	Absorption coefficients as the books print them, one row per finish.
materials.absorbers.datasheets	Sound absorption as a data sheet or a test report prints it.
materials.absorbers.carpets	Carpets, rated by their noise reduction coefficient and described by their pile.
materials.absorbers.layered	Declarative layer stacks and the transfer-matrix absorber solver.
materials.absorbers.biot	Biot poroelastic layers: the three waves and the 6x6 transfer matrix.
materials.absorbers.slow_sound	Slow-sound slit panels loaded with Helmholtz resonators (perfect absorbers).
materials.absorbers.suspended_ceilings	Suspended ceilings in a reverberation room: EN 16487:2014.
materials.diffusers.scattering_diffusion	Directional and random-incidence diffusion coefficients in a free field.
materials.diffusers.reverberation_room_scattering	Random-incidence scattering coefficient in a reverberation room.
materials.diffusers.design	Far-field polar response and diffusion coefficient predicted from a diffuser design.
materials.diffusers.metadiffuser	Metadiffusers: deep-subwavelength Schroeder-like sound diffusers.
materials.diffusers.measured_scattering	Scattering coefficients as the books print them, one row per surface.
materials.diffusers.predicted_diffusion	Normalized diffusion coefficients as a book computes them, one row per angle.
materials.diffusers.predicted_scattering	Scattering coefficients a book computed, kept apart from the ones measured.
materials.surfaces.road_absorption	In-situ sound absorption of road surfaces (ISO 13472-1 / ISO 13472-2).

Module	Summary
vibration.structural.mechanical_mobility	Mechanical mobility and the frequency-response-function family (ISO 7626-1:2011).
vibration.structural.point_mobility	Point mobilities and impedances of infinite structures (Cremer, Heckl & Petersson 2005, Chapter 5, Table 5.1).
vibration.structural.impact_mobility	Mechanical mobility measured by impact excitation (ISO 7626-5:2019).
vibration.structural.radiation_efficiency	Radiation efficiency of a plate in bending (Hopkins 2007, Sound Insulation, Section 2.9; Leppington et al. 1982; Maidanik 1962).
vibration.structural.junction_transmission	Bending-wave transmission coefficients for rigid plate junctions (Hopkins 2007, Sound Insulation, Section 5.2.1.3; Cremer et al. 1973; Craik 1981, 1996).
vibration.structural.experimental_sea	Experimental statistical energy analysis: coupling loss factors from measured energies (Norton & Karczub Ch. 6).
vibration.machinery.diagnostics	Kinematic fault frequencies of rotating machinery (Norton & Karczub Ch. 8).
vibration.machinery.evaluation	Evaluation of machine vibration by measurement (ISO 20816-1:2016).
vibration.structural.transfer_stiffness	Dynamic transfer stiffness of resilient elements (ISO 10846, Parts 1 to 5).
vibration.structural.building_damage	Effects of vibration on structures (DIN 4150-3:1999-02).
vibration.structural.building_response	Predicting the fundamental frequency of a building (ISO 4866 Annex D).
vibration.human.exposure	Human exposure to whole-body and hand-transmitted vibration.
vibration.human.multiple_shock	Whole-body vibration containing multiple shocks (ISO 2631-5:2018).
vibration.human.seat_vibration	What a seat does to the vibration under it (ISO 10326-1:2016).
vibration.human.instrumentation	Type-testing a human-vibration meter against ISO 8041-1:2017.
vibration.human.signal_burst	The saw-tooth signal burst of ISO 8041-1:2017, 5.9, and what a meter reads.
vibration.immission.vibration_meter	The vibration meter of DIN 45669-1:2010-09 (with Corrigendum 1:2012-12).
vibration.immission.railway	Evaluating the vibration of a passing train (DIN 45672-2:1995-07).
vibration.immission.ground	The elastic properties of the ground from its wave speeds (DIN 45672-1:2009-12).
vibration.immission.coupling	Mounting the transducer, and what the meter may be wrong by (DIN 45669-2:2005-06).
vibration.immission.people	Vibration and the people in a building (DIN 4150-2:1999-06).
vibration.immission.train_categories	Railway vibration by category of train (E DIN 4150-2:2023-08, 6.5.3).
vibration.immission.railway_prediction	Predicting railway vibration from third-octave spectra (E DIN 45672-3:2023-02).
vibration.immission.prediction	Predicting vibration before it is measured (DIN 4150-1:2001-06).

Module	Summary
environment.propagation.outdoor_propagation	Outdoor sound propagation: ISO 9613-2:1996 general method of calculation.
environment.sources.cnossos_road	CNOSSOS-EU road traffic source emission (Directive 2002/49/EC Annex II, 2.2).
environment.sources.statistical_pass_by	What a road surface adds to the noise of the traffic on it (ISO 11819-1:1997).
environment.propagation.ground_barriers	Spherical-wave ground effect and advanced barrier diffraction.
environment.propagation.ground_surfaces	Ground surfaces as the pages that print them print them.
environment.propagation.noise_reducing_devices	Single-number ratings of noise reducing devices (EN 1793, EN 16272).
environment.propagation.barrier_in_situ	What a barrier by the road is worth, measured (ISO 10847:1997).
environment.propagation.barrier_reflection	What a noise barrier sends back across the road, measured where it stands (EN 1793-5:2016).
environment.propagation.software_quality	Quality assurance of software for outdoor sound: a program’s results against the certified ones, and the spread of level differences (ISO 17534-1:2015).
environment.propagation.refraction	Atmospheric refraction: ray tracing and the parabolic equation (PE).
environment.propagation.air_absorption	Atmospheric absorption of sound: ISO 9613-1:1993.
environment.sources.cnossos_rail	CNOSSOS-EU railway source emission (Directive 2002/49/EC Annex II, 2.3).
environment.sources.rolling_stock_noise	The noise a railway vehicle emits, measured by ISO 3095:2013.
environment.sources.acoustic_roughness	The acoustic roughness of a rail, measured directly on it (EN 15610:2009).
environment.sources.track_decay	How fast vibration dies away along a rail (EN 15461:2008+A1:2010).
environment.assessment.impulsive_sound	Prominence of impulsive sounds and the LAeq adjustment (NT ACOU 112:2002, ISO/PAS 1996-3:2022).
environment.assessment.exposure_distribution	How often a blast is how loud: the distribution of its sound exposure level (ISO 13474:2009, clauses 4 and 5).
environment.assessment.rating	Environmental noise descriptors per ISO 1996-1:2016.
environment.sources.wind_turbine	Wind-turbine acoustic noise (IEC 61400-11:2012+A1:2018).
environment.assessment.wind_turbine_receptor	Wind turbine sound at a receptor (IEC TS 61400-11-2:2024).
environment.assessment.wind_turbine_modulation	Amplitude modulation of wind turbine sound at a receptor (IEC TS 61400-11-2:2024, clause 13).
environment.assessment.measurement	Determination of environmental-noise sound pressure levels (ISO 1996-2:2017).
environment.assessment.spain	Spanish noise regulation: the corrected level LKeq (Real Decreto 1367/2007).
environment.assessment.soundscape	How people hear a place: the soundscape questionnaire and its analysis (ISO/TS 12913-2:2018 Annexes A and C, ISO/TS 12913-3:2019 Annexes A and B).
environment.assessment.soundscape_binaural	What a soundscape sounds like at the ears: the binaural analysis of ISO/TS 12913-3:2019 Annex D and ISO/TS 12913-2:2018 Annex D.

Module	Summary
aircraft.certification	Aircraft noise certification: Effective Perceived Noise Level (ICAO Annex 16).
aircraft.atmospheric_absorption	One-third-octave-band atmospheric absorption for aircraft noise (SAE ARP 5534 and 866A).
aircraft.airport_noise	Noise-Power-Distance (NPD) event-level interpolation (ECAC Doc 29).
aircraft.anp_fleet	EASA ANP fleet database bridge for the ECAC Doc 29 airport-noise chain.
aircraft.npd_atmosphere	NPD data for a non-reference atmosphere (ECAC Doc 29 Vol. 2 Appendix D).
aircraft.flight_performance	ECAC Doc 29 flight performance: procedural steps into a flight profile.
aircraft.rotorcraft_noise	Rotorcraft noise by the hemisphere method (ECAC Doc 32 / NORAH2).
aircraft.rotorcraft_propagation	Rotorcraft propagation, ground effect and screening (ECAC Doc 32 / NORAH2).
aircraft.measurement_system	Aircraft-noise measurement-system tolerances (IEC 61265:1995).

Module	Summary
underwater.acoustics	Underwater-acoustics reference levels (ISO 18405:2017).
underwater.propagation.closed_form	Underwater sound propagation: propagation loss (closed-form).
underwater.propagation.weston_regimes	Weston’s shallow-water propagation regimes (flux theory).
underwater.propagation.sound_speed	Sound-speed profiles over a column of water.
underwater.sonar_equation	The sonar equation (passive and active), in decibels.
underwater.sources.ambient_noise	Ocean ambient-noise spectrum levels (Wenz framework).
underwater.propagation.seabed_reflection	Plane-wave reflection at the seabed (fluid-fluid Rayleigh model).
underwater.sources.ship_radiated_noise	Ship radiated noise and equivalent monopole source level (ISO 17208-1/-2).
underwater.sources.ship_traffic_noise	Predicted source-level spectrum of shipping traffic (semi-empirical models).
underwater.sources.pile_driving_noise	Radiated underwater sound from percussive pile driving (ISO 18406:2017).
underwater.bioacoustics.audiograms	Marine-mammal hearing thresholds (group audiograms and the orca audiogram).
underwater.bioacoustics.weighting	Regulatory auditory weighting and exposure criteria for marine mammals.
underwater.propagation.numerical	Numerical models of underwater sound propagation (range-independent water, with an optionally sloping bottom for the ray-based solvers).

Module	Summary
emission.sound_power	Sound power level of a noise source from sound pressure measurements over an enveloping measurement surface: ISO 3744:2010 (engineering, accuracy grade 2) and ISO 3746:2010 (survey, accuracy grade 3).
emission.sound_power_anechoic	Sound power level of a noise source in an anechoic or hemi-anechoic room, from sound pressure measurements over an enveloping surface: ISO 3745:2012 (precision, accuracy grade 1).
emission.free_field_qualification	Qualification of an anechoic or hemi-anechoic room by the inverse square law: ISO 26101:2017, with the criteria of ISO 3745:2012 Annex A as Amendment 1:2017 rewrote it.
emission.reference_sound_source	Reference sound sources: the performance requirements and the calibration of ISO 6926:2016.
emission.sound_power_intensity	Sound power level of a noise source by sound-intensity scanning: ISO 9614-2:1996 (engineering, grade 2; survey/control, grade 3) and ISO 9614-3:2002 (precision, grade 1).
emission.sound_power_intensity_points	Sound power level of a noise source from sound intensity measured at discrete points: ISO 9614-1:1993.
emission.sound_power_reverberation	Sound power level of a noise source measured in a reverberation test room: ISO 3741:2010 (precision method, accuracy grade 1).
emission.sound_power_in_situ	Sound power and sound energy levels of a noise source determined in situ by comparison with a reference sound source: ISO 3747:2010 (engineering grade 2 and survey grade 3).
emission.sound_power_hard_walled	Sound power and sound energy levels of a small movable source in a hard-walled test room, by comparison with a reference sound source: ISO 3743-1:2010 (engineering grade 2).
emission.sound_power_special_room	Sound power level of a small movable source in a special reverberation test room: ISO 3743-2:2018 (engineering grade 2), the direct method and the comparison method.
emission.sound_power_in_duct	Sound power radiated into a duct by a fan, in-duct method: ISO 5136:2003.
emission.sound_power_plant	Sound power levels of multisource industrial plants for the evaluation of sound pressure levels in the environment: ISO 8297:1994, engineering method (grade 2).
emission.sound_power_high_frequency	Sound power levels in the 16 kHz octave band: ISO 9295:2015.
emission.turbine_noise	Airborne noise of a steam turbine set and its driven machinery: IEC 61063:1991 (EN 61063:1996).
emission.intensity	Two-microphone (p-p) sound intensity per IEC 61043:1993 and the ISO 9614-1:1993 field indicators.
emission.intensity_compliance	IEC 61043:1993 sound-intensity instrument class verification.
emission.vibration_sound_power	Airborne sound power from surface vibration (ISO/TS 7849-1/-2:2009).
emission.workstation	What the ISO 11200 group shares: the emission sound pressure level at a work station, its two corrections and its uncertainty.
emission.declaration	ISO 4871:1996 declaration of noise emission values of machinery and equipment.

Module	Summary
electroacoustics.distortion	Harmonic distortion of electroacoustic equipment (IEC 60268-3 / AES17).
electroacoustics.intermodulation	Intermodulation distortion of audio equipment (IEC 60268-3 14.12.7-10).
electroacoustics.noise_measurements	Noise measurements of audio equipment (AES17-2015 6.4).
electroacoustics.frequency_response	Frequency-response and coherence estimators (Bendat & Piersol).
electroacoustics.swept_sine	Harmonic-distortion separation with exponential sweeps (Farina / Novak).
electroacoustics.piston	Radiation of a rigid circular piston set in an infinite baffle.
electroacoustics.loudspeaker	Rated loudspeaker characteristics (IEC 60268-5).
electroacoustics.microphone	Rated microphone characteristics (IEC 60268-4).
electroacoustics.sound_reinforcement	Gain before feedback of a sound-reinforcement system.
electroacoustics.induction_loop	Audio-frequency induction-loop systems for hearing aids: the performance of an installed system.
electroacoustics.induction_loop_components	Components of an audio-frequency induction-loop system: the loop, its amplifier, the neck loop.
electroacoustics.programme_signal	The simulated programme signal of IEC 60268-1:1985, Clause 7.
electroacoustics.headphones	Headphones and earphones: the characteristics of IEC 60268-7:2010 that are computations.

Module	Summary
noise_control.silencers	Reactive silencers by the four-pole (transmission-matrix) method.
noise_control.silencer_measurement	Insertion loss of a ducted silencer, measured by substitution.
noise_control.hvac	HVAC duct acoustics: fan power, duct losses, plenums and flow-generated noise.
noise_control.duct_path	End-to-end duct-borne noise calculation: fan to room, element by element.
noise_control.duct_modes	Higher-order acoustic modes in ducts, with the mean-flow cut-on shift.
noise_control.duct_walls	What a duct wall does to sound, out of it and into it.
noise_control.enclosures	Insertion loss of a close or free-standing machine enclosure.
noise_control.enclosure_insulation	What an enclosure is worth, measured rather than predicted (ISO 11546).
noise_control.cabin_insulation	What a cabin keeps out, measured in the room it stands in (ISO 11957).
noise_control.silencer_in_situ	What a silencer does where it was installed (ISO 11820:1996).
noise_control.screen_in_situ	What a screen on the shop floor is worth (ISO 11821:1997).
noise_control.room_to_room	Room-to-room noise reduction: source room, partition, receiving room, criterion.
noise_control.valves	Control valve aerodynamic noise (IEC 60534-8-3:2010).
noise_control.valves_hydrodynamic	Control valve hydrodynamic noise (IEC 60534-8-4:2005).

Module	Summary
broadcast.program_loudness	Programme loudness and true-peak level (ITU-R BS.1770-5, EBU R 128).
broadcast.quasi_peak	Psophometric quasi-peak programme-level meter (ITU-R BS.468-4 clause 2).

Module	Summary
simulation.fdtd	2D acoustic finite-difference time-domain (FDTD) simulation.
simulation.ntff	2D near-to-far-field (NTFF) transformation over a closed contour.
simulation.elastic_fdtd	2D elastic finite-difference time-domain (P-SV) simulation.