Built-in electric anti-aliasing filter ensuring correct sampling of the measured signal.
Built-in antialiasing filter. On-chip digital filter of the analogue-to-digital converter, ensuring correct sampling of
the measured signal.
Pass band (-3 dB) 11.3 kHz
Stop band 14.4 kHz
Attenuation in the stop band > 50 dB
Sampling frequency 24 kHz
Analogue to digital converter sigma-delta 24 bit
Input attenuator accuracy
0.1 dB (for f = 1 kHz and T = +23°C)
Internal oscillator accuracy 0.01 % (for f = 1 kHz and T = +23°C).
Digital Filters
Weighting filters
• A meeting requirements of the IEC 61672-1:2013 standard for the Class 1 “A” filter,
• C meeting requirements of the IEC 61672-1:2013 standard for the Class 1 “C” filter,
• Z meeting requirements of the IEC 61672-1:2013 standard for the Class 1 “Z“ filter,
• B meeting IEC651 for the Type 1 filter
See Chapter C.5 for the A, C, B and Z filter characteristics,
Noise levels (measured with the SL 973 and source impedance 50 Ω, Microphone compensation switched-
off)
”Z” weighting < 7.1 µV
RMS
(30 dB)
”A” weighting < 2.2 µV
RMS
(20 dB)
”C” weighting < 2.2 µV
RMS
(20 dB)
”B” weighting < 2.2 µV
RMS
(20 dB)
1/1 Octave filters 9 filters with centre frequencies from 31.5 Hz to 8 kHz (base 10), meeting
IEC 61260-1:2014 standard for Class 1.