G.R.A.S. 45CA User Manual

Fig. 5.1 Both assembly options for tests using the IEC 60318 Ear Simulator RA0039
½" to ¼" Adapter
GR0010
(supplied with the
¼"preampliers)
¼"Preamplier
Type 26AC *
Adapter
RA0176
½" Externally
Polarized
Microphone
Type 40AG
5 CongurationwithIEC60318EarSimulatorRA0039
This ear simulator can be used with
• ½"ExternallyPolarizedPressureMicrophoneType40AG
• ½"PrepolarizedPressureMicrophoneType40AO.
Applications
Monaural or binaural measurements of
• Hearingprotectiondevices:Ear muffs (supra-aural, circum-aural)
• Soundsources:Headphones (supra-aural, circum-aural).
Note: As the coupler is not for use with a pinna simulator, it cannot be used for testing
ear-inserts (earphones and earplugs).
RequiredAccessories
• The items of one of the two assembly options shown in Fig. 5.1
• Pistonphone Type 42AP (recommended) or Type 42AA
• Test equipment such as the instruments shown in Fig. 5.15
5.1 EarSimulator/PreamplierAssembly
Fig.5.1displaysthetwooptionsforcongurationwithEarSimulatorRA0039.
Note: Do not assemble the parts yet - proceed to Section 5.2 Calibration.
ExternallyPolarizedMicrophone    PrepolarizedMicrophone
¼" CCP
Preamplier
Type 26CB *
½"Prepolarized
Microphone
Type 40AO
IEC 60318
Ear Simulator
RA0039
_____________
* For space limitations, ¼"PreamplierType26AC/Type26CB(shown)canbeusedformonauralmeasurementsonly. 
For binaural measurements, replace Type 26AC with Type 26AS and Type 26CB with Type 26CS.
G.R.A.S. SOUND & VIBRATION
Page 16
Hearing-Protector Test Fixture Type 45CA

G.R.A.S. 45CA Specifications

General

Brand	G.R.A.S.
Model	45CA
Category	Protection Device
Language	English