General Tools and Instruments DSM8921 - Manual (Page 6)

SELECTING A AND C WEIGHTING
When you turn the meter on, it will be in
A weighting mode.
A weighting enables the meter to
respond in the same manner as the
human ear, which increases and
decreases amplitude over the
frequency spectrum.
Applications for A weighting include
OSHA regulatory testing, environ-
mental measurement, workplace
design, and law enforcement.
C weighting is suitable for flat response
measurements with no increase or
decrease of amplitude over the
frequency spectrum. Applications for
C weighting include the sound level
analysis of engines and machinery.
Press the C/A key to toggle between A
and C weighting. A small A or C will be
displayed on the right side of the screen
to indicate the current mode.
Fig.3
40
SPL
+10