Svantek SVAN 948 - 1;3 OCTAVE Analyser of Acoustic Signal

SVAN 948 USER MANUAL
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4.5.1. 1/3 OCTAVE analyser of acoustic signal
In order to select the instrument’s acoustic mode the user has to enter the CHANNELS SETUP
list by pressing the <MENU> push-button, selecting by means of the <

>, <

> (or <

>, <

>) push-
buttons the INPUT text and pressing the <ENTER>, and then enter the CHANNELS SETUP the same
way like in previous and chose number of CHANNEL to configuration. In the MODE sub-list the user can
select the kind of input signal which has to be measured or analysed by the instrument. In the case of
acoustic signals the SOUND METER option should be selected Then by pressing <

>, <

> push-
buttons user has to change SOUND mode and press the <ENTER> push-button, which closes the MODE
sub-list. The MODE sub-list is closed ignoring any changes made in it, after pressing in any time the
<ESC> push-button.
a)
b) c)
The view of the displays in the CHANNEL x (path: MENU / INPUT) list with the CHANNEL x text selected (a);
the VIBR. METER mode selected (b) and the SOUND METER mode selected (c)
The instrument’s operation as 1/3 OCTAVE analyser is similar to the SLM measurement mode.
1. In 1/3 OCTAVE analysis the spectrum is available in parallel to the SLM operation. All 45 digital pass-
band filters (with the centre frequencies from 20 kHz down to 0.8 Hz; in base two system) are working
in the real time with the weighting filters: HP, LIN, A or C selected in the SPECTRUM of the
1/3 OCTAVE SETUP sub-list, user has to select number of CHANNEL to configure the filter, and the
linear RMS detector. Additionally, the TOTAL RMS values for the full frequency range with the A, C
and LIN (Z) weightings are displayed. In order to inform the user about the working mode of the
instrument, in one profile and 3 PROFILES modes of result’s presentation the doted line are used for
the indication that the instrument do not work in the SLM mode. In the SLM mode the continuous
lines are used.
The view of the displays in one profile and 3 PROFILES result’s presentation mode with the doted lines
indicating that the instrument do not work in the SLM mode
Notice: The TOTAL RMS results are measured with the weighting filters: A, C and LIN
without taking into account the setting of the SLM profiles. The spectra are always linearly averaged.
Thus, the TOTAL values from 1/3 OCTAVE analysis can be different from those obtained for the SLM
profiles (if the RMS INTEGRATION (path: MENU/ SETUP/ RMS INTEGRATION) was set as EXPONENTIAL).
2. As 1/3 OCTAVE analyser the instrument operates in two input ranges 105 dB and 130 dB, which can
be selected by means of the RANGE position.