Manual

Sound Pressure Level: The equivalent continuous sound pressure level
(also time-averaged sound level) is indicated in dBL
eq
, dBL
Aeq
, dBL
Ceq
,
depending on the selected filter in the filter menu.
Example:
• select in the main menu the filter A-WTD
• the measurement unit is changing to dBL
Aeq
and the minimum,
maximum and actual sound pressure level readings below are A-
weighted.
Below the time-averaged SPL reading one of the following values
may be displayed (select with the cursor keys):
• ACT: actual sound pressure level (SPL)
• MIN: minimum sound pressure level acquired during the measuring
time indicated by the clock. The minimum value is stored until a
new lower reading has been taken.
• MAX: maximum sound pressure level acquired during the
measuring time indicated by the clock. The maximum value is
stored until a new higher reading has been taken.
Pause: The L
eq
and min./max. measurement may be freezed for a user
defined time.
• Select the pause symbol and press the enter key.
• The pause symbol is flashing.
• The actual SPL reading is continuously displayed and not freezed.
• Select the pause symbol and press the enter key to continue the
measurement, visible by the continuing counting clock.
Clock: Duration in hours:minutes:seconds of the actual measurement;
select the clock and press the enter key to reset the time and restart
the measurement.
Time weighting: All sound pressure level measurements include time
weighting. A change in sound pressure level is read out on the display
with a shorter or longer response time.
Available response times, corresponding to IEC 60651, are
• SLOW (long attack- and release time)
• FAST (short attack- and release time)
• IMP (=impulse, very short attack and long release time)
Bargraph: The bargraph provides an analog display of the actual sound
pressure level.
Available bargraph ranges are:
• 20 - 100 dB
SPL
• 40 - 120 dB
SPL
• 60 - 140 dB
SPL
The selected bargraph range complies to the measurement range of
the instrument. To achieve accuracy of the measurement within the
specified tolerances the proper range must be selected, called primary
indicator range. The two range indicator arrows assist to set the
Minilyzer to the optimal range. As soon as the indicated bargraph
value is found lower than the primary indicator range, the down arrow
symbol below RNGE will start to move, symbolizing the actual bargraph
reading is inaccurate. The lower bargraph range needs to be changed
manually by selecting the moving left arrow symbol and pressing the
enter key.
By exceeding the primary indicator range four overload arrows
replacing the dBL
eq
reading and no reading below is shown (see Fig.
13). Select the right arrow below RNGE and press enter to change to
the next higher bargraph range. In case signal clipping has occurred
the term OVL is flashing above the RNGE field as long as this peak, is
significant influencing the integrating sound pressure level reading.
For example an SPL peak for 0.1 sec. will have effects to the L
eq
reading
for several seconds but it’s contribution can be neglected after ten
minutes.
Measurement Functions Measurement Functions
3-04 3-05
Fig 13 SPL Panel with Overload