SVL Get dB Reference VI

SVL Get dB Reference VI

Owning Palette: Scaling & Calibration VIs

Requires: Sound and Vibration Toolkit

Returns the dB reference stored in the waveform attributes of the scaled signal input. The dB reference is set by the DAQ Assistant for Sound Pressure and Acceleration tasks, the SVL Scale Voltage to EU VI, and the SVL Set dB Reference VI. The dB reference is used for all downstream conversions to dB. Wire data to the scaled signal [EU] input to determine the polymorphic instance to use or manually select the instance.

Details  

SVL Get dB Reference (1 Ch)

	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	scaled signal [EU] returns the unchanged scaled signal. t0 returns the start time of the waveform. dt returns the time interval, in seconds, between data points in the waveform. Y returns the data values of the waveform.
	dB reference [EU] returns the dB reference stored in the waveform attributes of scaled signal [EU]. dB reference [EU] returns 1.0 if the dB reference attribute is not found.
	error out contains error information. This output provides standard error out functionality.

SVL Get dB Reference (N Ch)

	scaled signals [EU] specifies the scaled signals expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define virtual channels in National Instruments Measurement & Automation Explorer (MAX). t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	scaled signals [EU] returns the scaled signals expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 returns the start time of the waveform. dt returns the time interval, in seconds, between data points in the waveform. Y returns the data values of the waveform.
	dB references [EU] specifies the dB references to add to the waveform attributes. The specified dB references overwrite existing references.
	error out contains error information. This output provides standard error out functionality.

SVL Get dB Reference Details

The dB reference, reference, can be used to convert a measurement result, value, to dB by the following equation:

dB = 20 * log₁₀(value / reference) = 10 * log₁₀(value / reference)²