Measurement views, User settings, Ge 48 – Casella CEL CEL-63X User Manual
Page 48

CEL-63x Environmental & Occupational Noise Meter
48
Casella CEL
4.4 Measurement views
User settings
The CEL-63x instrument has two measurement views that are available for
user-defined settings. These measurement views are called User 1 and User 2.
Refer to “
” on page 18 for instructions to use
these settings.
When you select one of the user-defined views, you can change the following
settings:
Microphone response
The setting options are for a Random or for a Free field microphone
response.
True random field and free-field conditions do not exist in normal
environments. The response patterns measured are close approximations to the
theoretical measurements under the defined conditions.
Random field
A random-field microphone response is often necessary to conform to US
regulations.
A random-field response is where sound energy is distributed uniformly
throughout the space being measured.
Free field
A free-field microphone response is generally necessary to conform to
regulations throughout the European Union.
A free-field response is where sound propagates directly from a source to a
microphone without any form of obstruction.