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Owning Palette: Sound Quality VIs

Installed With: Sound and Vibration Measurement Suite

Computes stationary loudness from the sound pressure signal waveform or the 1/3-octave band spectrum calculated over the frequency range 25 Hz to 12.5 kHz. Wire data to the sound pressure signal input to determine the polymorphic instance to use or manually select the instance.

Because stationary loudness measurements use linear averaging, stationary loudness is most applicable to steady-state noises or signals that do not vary with time. Stationary loudness is also known as ISO 532B loudness and Zwicker loudness.

This VI measures the 1/3 octave spectrum, combines the fractional-octave bands into critical bands, and then applies spectral masking. The VI returns the result as the specific loudness versus critical band rate, and then integrates the specific loudness to measure the total loudness and loudness level. This VI calculates the stationary loudness in compliance with ISO 532B, DIN 45631, and other standards.

Use the pull-down menu to select an instance of this VI.

Select an instance SV Stationary Loudness (Time) (1 Ch)SV Stationary Loudness (Octave) (1 Ch)

SV Stationary Loudness (Time) (1 Ch)

	diffuse field specifies if the sound field is diffuse (TRUE) or a free field (FALSE). The default is free field (FALSE).
	sound pressure signal [Pa] specifies the sound pressure signal in Pascals. t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	specific loudness returns the specific loudness at the critical band rate. The critical band rate is in units of bark. You can wire this output to the specific loudness input of the Loudness instance of the SV Aures Sharpness VI.
	loudness [Sone] returns the perceived loudness in units of Sones.
	loudness level [Phon] returns the perceived loudness level in units of Phons.
	loudness info returns information about the loudness measurement. You can wire this output to the loudness info input of the Loudness instance of the SV Aures Sharpness VI. x-axis units returns the units of the x-axis. The valid values are Frequency, Critical Band, and Critical Band Rate. x-axis unit label returns the label of the x-axis. y-axis units returns the units of the y-axis. The valid values are Band Power, Level, Loudness, Sharpness, Roughness, Fluctuation Strength, and Tonality. y-axis unit label returns the label of the y-axis. data attributes returns information about the sound quality measurements this VI analyzes.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

SV Stationary Loudness (Octave) (1 Ch)

	diffuse field specifies if the sound field is diffuse (TRUE) or a free field (FALSE). The default is free field (FALSE).
	octave spectrum specifies the octave spectrum to perform the operation on, in band power versus nominal frequencies. nominal frequencies [Hz] specifies the nominal, or preferred, frequencies as opposed to the exact frequencies associated with each 1/n octave band. band power specifies the band power in decibels associated with each 1/n octave band.
	octave info contains information about the octave spectrum that you can pass from another VI. Do not change the values in octave info. If you want to view the information, you can right-click the octave info wire and select Custom Probe»Octave Info from the shortcut menu.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	specific loudness returns the specific loudness at the critical band rate. The critical band rate is in units of bark. You can wire this output to the specific loudness input of the Loudness instance of the SV Aures Sharpness VI.
	loudness [Sone] returns the perceived loudness in units of Sones.
	loudness level [Phon] returns the perceived loudness level in units of Phons.
	loudness info returns information about the loudness measurement. You can wire this output to the loudness info input of the Loudness instance of the SV Aures Sharpness VI. x-axis units returns the units of the x-axis. The valid values are Frequency, Critical Band, and Critical Band Rate. x-axis unit label returns the label of the x-axis. y-axis units returns the units of the y-axis. The valid values are Band Power, Level, Loudness, Sharpness, Roughness, Fluctuation Strength, and Tonality. y-axis unit label returns the label of the y-axis. data attributes returns information about the sound quality measurements this VI analyzes.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.