The GRAS RA0038 Coupler is a standard 2 cm³ Coupler according to IEC 126 and ANSI S3.7-1973. It uses a ½" microphone (preferably the GRAS 40AG) with a suitable preamplifier (e.g. GRAS 26AC which is a ¼" preamplifier but is supplied with an adapter for ½" microphones).
Technology
The RA0038 is for use in the acoustical measurements of insert type hearing aids and earphones.
It complies with the requirements of
- IEC 60318-5 (60126) 2 cm3 coupler for the measurement of hearing aids and earphones coupled to the ear by ear inserts and
- ANSI S3.7-1995 American National Standard for Coupler Calibration of Earphones.
To avoid possibly damaging the microphone, the RA0038 can be used with a microphone fitted with its protection grid, e.g. a GRAS 40AG and a suitable preamplifier, like GRAS 26AS which is a 1/4" very short preamplifier with 3 m integrated cable.
The RA0038 is also part of the GRAS 43AB Artificial Ear.
Specifications
| Connector type |
– |
BNC |
| Polarization/Connection |
– |
0 V / CCP |
| Coupler volume |
ccm |
2 |
| Non-condensing humidity range |
% RH |
0 – 95 |
| ANSI standard |
– |
S3.7 |
| IEC standard |
– |
60318-5 (formerly 60126) |
| CE/RoHS/WEEE compliant |
– |
Yes/Yes, Yes |
| Weight |
g / oz |
50 / 1.76 |
