When combined with any DSA device, the weighting filter used by the SVT A, B, C Weighting Filter (Fixed Rates) VI or designed by the SVT Weighting Filter VI complies with the following standards:
The SVT Weighting Filter VI accommodates any sample rate greater than 4 kHz and designs the filter coefficients to target the attenuation curves defined by the ANSI standards. Given the selected sampling frequency, compliance with a particular filter type, either Type 1 or Type 0, is ensured up to a specific frequency. This frequency is the maximum frequency within tolerances. Use the SVT Max Frequency Within Tolerances [ANSI] VI to determine the maximum frequency within tolerances. The SVT A, B, C Weighting Filter (Fixed Rates) VI supports the following sample rates:
4 kHz, 8 kHz, 10 kHz, 11.025 kHz, 12.8 kHz, 20 kHz, 22.05 kHz, 25.6 kHz, 40 kHz, 44.1 kHz, 48 kHz, 50 kHz, 51.2 kHz, 80 kHz, 96 kHz, 100 kHz, 102.4 kHz, 192 kHz, 200 kHz, 204.8 kHz, 500 kHz, 1 MHz
For all supported sample rates the VI achieves Type 0 compliance to the Nyquist frequency.
Use the SVT A, B, or C Weighting Filter (Fixed Rates) VI or the SVT Weighting Filter VI to apply an A-, B-, or C-weighting filter to time-domain signals. When combined with any DSA device, the weighting filter used by the SVT A, B, or C Weighting Filter (Fixed Rates) VI or designed by the SVT Weighting Filter VI complies with:
The SVT Weighting Filter VI accommodates any sample rate greater than 4 kHz and designs the filter coefficients to target the attenuation curves defined by the IEC standards. Given the selected sampling frequency, compliance with a particular filter type, either Class 2 or Class 1, is ensured up to a specific frequency. This frequency is the maximum frequency within tolerances. Use the SVT Max Frequency Within Tolerances [IEC] VI to determine the maximum frequency within tolerances. The SVT A, B, C Weighting Filter (Fixed Rates) VI supports the following sample rates:
4 kHz, 8 kHz, 10 kHz, 11.025 kHz, 12.8 kHz, 20 kHz, 22.05 kHz, 25.6 kHz, 40 kHz, 44.1 kHz, 48 kHz, 50 kHz, 51.2 kHz, 80 kHz, 96 kHz, 100 kHz, 102.4 kHz, 192 kHz, 200 kHz, 204.8 kHz, 500 kHz, 1 MHz
For all supported sample rates the VI achieves Class 1 compliance to the Nyquist frequency.
When combined with any DSA device, the weighting filter used by the SVT Radiocommunications Weighting Filter (Fixed Rates) VI complies with the ITU-R 468-4 standard. The SVT Radiocommunications Weighting Filter (Fixed Rates) VI accommodates the following sample rates:
20 kHz, 22.05 kHz, 25.6 kHz, 40 kHz, 44.1 kHz, 48 kHz, 50 kHz, 51.2 kHz, 80 kHz, 96 kHz, 100 kHz, 102.4 kHz, 192 kHz, 200 kHz, 204.8 kHz, 500 kHz, 1 MHz
For all supported sample rates, the VI achieves compliance to the Nyquist frequency.
When combined with any DSA device, the weighting filter used by the SVT Telecommunications Weighting Filter (Fixed Rates) VI complies with the following standard and reference:
The SVT Telecommunications Weighting Filter (Fixed Rates) VI supports the following sample rates:
4 kHz, 8 kHz, 10 kHz, 11.025 kHz, 12.8 kHz, 20 kHz, 22.05 kHz, 25.6 kHz, 40 kHz, 44.1 kHz, 48 kHz, 50 kHz, 51.2 kHz, 80 kHz, 96 kHz, 100 kHz, 102.4 kHz, 192 kHz, 200 kHz, 204.8 kHz, 500 kHz, 1 MHz
For all supported sample rates, the VI achieves compliance to the Nyquist frequency.
When combined with any DSA device, the human vibration weighting filters that the Sound and Vibration Measurement Suite provides comply with ISO 8041:2005 (E): Human Response to Vibration – Measuring Instrumentation.
The Sound and Vibration Measurement Suite provides the following weighting filters that you can apply to human vibration signals:
The Octave Analysis VIs can accommodate any sampling frequency and any number of fractional-octave bands. These VIs offer compliance with the following standards:
According to the IEC 61260:2014 and the ANSI S1.11-2014 standards, the exact mid-band frequencies, fm, of any filter in a set of filters shall be determined from the following expression:
fm = frGx/b, when b is odd
fm = frG(2x + 1)/2b, when b is even
Where fr is the reference frequency, G = 100.3 is the octave frequency ratio, 1/b is the bandwidth designator, and equals 1 for octave, 1/3 for 1/3 octave, 1/6 for 1/6 octave, 1/12 for 1/12 octave, and 1/24 for 1/24 octave, x is any integer, positive or negative, or zero.
The exact midband frequencies are used to design the filters for fractional-octave analysis. However, all the octave analysis tools in the Sound and Vibration Measurement Suite return the nominal midband frequencies, also called the preferred frequencies. In the case of octave and 1/3 octave analyses, the nominal frequencies are calculated in accordance with the ANSI and IEC standards. In the case of 1/6, 1/12, and 1/24 octave analyses, the nominal frequencies are calculated in accordance with the Annex E (informative) of the IEC 61260:2014 and the ANSI S1.11-2014 standards.
When combined with any National Instruments DSA device, the appropriate microphone, and proper signal conditioning, the filters produced by the octave analysis tools in the Sound and Vibration Measurement Suite comply with the following standards:
For octave filters, choose a sampling frequency at least three times the exact center frequency of the highest frequency band. For fractional-octave filters, choose a sampling frequency at least 2.5 times the exact center frequency of the highest frequency band.
When combined with any National Instruments DSA device, the appropriate microphone, and proper signal conditioning, the Sound Level VIs are compliant with the ISO/IEC 61672-1:2002 standard.
National Instruments dynamic signal acquisition boards combined with the NI LabVIEW Sound and Vibration Software, have been tested and found compliant with several ANSI and IEC standards including the requirements for a class 1 instrument specified in IEC 61672-1: 2002. The filters used meet the requirements for a class 1 instrument specified in IEC 61260: 1995.
For a complete system, a suitable microphone compatible with ANSI S1.4 or IEC 651 requirements for a Type 1 precision microphone needs to be specified.