Acoustic Standards Compliance
The National Instruments LabVIEW Sound and Vibration Toolkit 4.0 meets the following standards for measurement and analysis. All information is compiled from the Sound and Vibration Toolkit User Manual, August 2005.Table of Contents:
Complete List of Standards
Detailed Information
Certificates of Compliance
Complete List of Standards
I. Weighting Filters
a. A-, B-, and C-Weighting Filters
i. ANSI S1.4-1983
ii. ANSI S1.42-2001
iii. IEC 61672-1:2002
b. Radiocommunications Weighting Filters
i. ITU-R 468-4
ii. Dolby
c. Telecommunications Weighting Filters
i. ITU-T 0.41 (CCITT)
ii. Bell System Technical Reference 41009 (C-message)
II. Octave Analysis
a. ANSI S1.11-2004, class 1
b. IEC 1260:1995, class 1 (also IEC 61260)
III. Sound Level
a. ISO/IEC 61672-1:2002
b. IEC 651 (when used with appropriate microphone)
c. IEC 61260: 1995
d. ANSI S1.4
Detailed Information
I. Weighting Filters
a. A-, B-, and C-Weighting Filters
i. ANSI Standards - 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:
· ANSI S1.4-1983
· ANSI S1.42-2001
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 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.
ii. ISO/IEC Standard - 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:
· IEC 61672-1:2002
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 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.
b. Radiocommunications Weighting Filters
i. ITU-R 468-4 - 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.
ii. Dolby
c. Telecommunications Weighting Filters
i. 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:
· ITU-T 0.41 (CCITT)
· Bell System Technical Reference 41009 (C-message)
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.
II. Octave Analysis
a. Overview - The Octave Analysis VIs can accommodate any sampling frequency and any number of fractional-octave bands. These VIs offer compliance with the following standards:
· ANSI S1.11-2004, class 1
· IEC 1260:1995, class 1
b. Midband Frequencies - According to the IEC 1260:1995 and the ANSI S1.11:2004 standards, the midband frequency, or center, frequency of the bandpass filter is defined by the following equations:
fi = 1000 * 2ib for 1/N octave filters when N is odd
fi = 1000 * 2(i+1)b/2 for 1/N octave filters when N is even
where
fi is the center frequency of the ith band-pass filter expressed in hertz.
i is an integer when i = 0, f0 = 1 kHz, which is the reference frequency for the audio range.
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.
c. Nominal Frequencies - The exact midband frequencies are used to design the filters for fractional-octave analysis. However, all the Octave Analysis VIs 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 A (informative) of the IEC 1260:1995 and the ANSI S1.11:2004 standards.
d. Compliance with ANSI and IEC Standards - When combined with any National Instruments DSA device, the appropriate microphone, and proper signal conditioning, the filters produced by the Octave Analysis VIs comply with the following standards:
· ANSI S1.11-2004: Specification for octave-band and fractional-octave-band analog and digital filters, class 1
· IEC 1260 (1995 - 07): Electroacoustics - Octave-band and fractional-octave-band filters, class 1
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.
III. Sound Level
a. 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.
b. IEC 651 defines four classes of accuracy for a sound level meter, with Type 0 being the most accurate and Type 3 being the least accurate. Type 1 sound level meters are the most widely used sound level meters in practice. Detailed requirements for a sound level meters are given in ANSI S1.4 (SVT compliant) and IEC Publications 651 and 804.
c. National Instruments dynamic signal acquisition boards combined with the NI LabVIEW Sound and Vibration Toolkit, 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.
d. 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.
Certificates of Compliance
I. Weighting Filters
weighting_Filters_Certificate.pdf
II. Octave Analysis
Octave Analysis_Certificate.pdf
III. Sound Level
Sound Level_Certificate.pdf
Related Links:
Measurement Encyclopedia - Acoustic Standards good , very kind Thank you Very much Thank you Very much:victory: 怎么没有了？ lz真好，赞扬
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