Casella CEL CEL-281 - Manual (Page 2)

Page ii - CEL-281 Operator's Handbook
Supplementary Information - July 1996
Revised Microphone Arrangements
Since this handbook was prepared, a redesigned microphone arrange-
ment has come into use.
1. The current instrument features a redesigned microphone
arrangement with a 1/4" diameter microphone housing replac-
ing the microphone in a 9 mm (3/8") housing described in this
handbook which was used on earlier instruments.
In consequence, the CEL-4725 1/4" Microphone Coupler
required during acoustic calibration (and supplied with CEL-282
and CEL-284/2 Calibrators) should now be used. The CEL-6050
Microphone Coupler used with the earlier microphones is no
longer included.
2. Due to other minor changes in the microphone assembly, the
calibration level for all CEL 1/4" microphones has been changed
to 113.6 dB from the 114.0 dB previously quoted.
When an instrument has 1/4" microphone, or a replacement 1/4"
microphone supplied after 1-1-96,
USE THE 113.6 dB CALIBRATION LEVEL.