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3
Design features
3.1
Acoustical quantities
The S50 Sound Level Meter has a number of pre-defined
measurement standards, each including any of the pairs
L
max
and L
eq
L
peak
and L
eq
where
L
max
:
The highest RMS reading over the selected interval time.
L
peak
:
The absolute peak value over the selected interval time.
Measurement of L
peak
is normally used in the protection of
humans’ hearing against sudden large pressure peaks.
L
eq
:
The time-averaged sound pressure level over the selected
interval time (see below). It has the formal symbol
L
AT
(IEC
61672-1), but for mainly historical reasons
L
AT
is commonly
referred to as
L
eq
. It is usually called
the
equivalent sound level
.
3.2
Frequency weightings
S50 Sound Level Meter handles both A- and C-frequency weighting
filtering. One of these frequency weightings can be selected at a
time.
3.3
Time weightings
S50 Sound Level Meter handles two time constants:
0.125 seconds for time weighting F (FAST)
1 second for time weighting S (SLOW)
One of the time weightings can be selected at a time.
Summary of Contents for 080-02850-0
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