Lencore Spectra Classic: Installation and Operations Manual - Manual (Page 7)

It takes approximately 30 seconds for meter to respond to sound. 0 to
50 dB...you want the reading to be to the left of the 0. -10 would be 40
dB. You need a reading between -2.5 and 1.5 on the meter. This would
be 47.5 to 48.5dB. It would naturally be high with the ceiling open.
instructions for using the simpson model 884-2
(or equivalent sound meter)
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Turn large round dial to 50.
Make sure fast/slow setting is on slow.
Hold meter approximately 4’ above floor.
Note meter reading after one minute.
Approximately 2 weeks after install, or when ceiling tiles
and furniture are all in place, reset units to 47.5 to 48.5 dB
four feet above floor.
section 1
1.4 | sound meter
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