For microphones

The GRAS 67TS Turbulence Screen Kit is designed for aeroacoustic testing in solid-walled wind tunnels. The hydrodynamic component of turbulence is attenuated up to 25 dB. Thereby the acoustic signals of interest can be identified and diagnosed with a reliable resolution.

Microphone clips 12 mm and 25 mm for side-by-side mounting of a pair of 1/4” intensity microphones.

The GRAS AL0013 is an adapter for mounting a microphone set (microphone/preamplifier) on tripods having a standard 1/4” UNC-20 male thread. The adapter is provided with a clamp for attaching a 1/4" diameter preamplifier.

AM0069 contains 5 spherical windscreens for 1/2" microphones optimized for sound pressure measurements under free-field conditions.

AM0071 contains 5 spherical windscreens for 1/4" microphones optimized for sound pressure measurements under free-field conditions.

AM0363 contains 5 spherical windscreens for 1" microphones optimized for sound pressure measurements under free-field conditions.

AM0364 contains 6 spherical windscreens optimized for 1/4" dedicated array microphones, or other 1/4" microphone sets mounted in array modules PR0001 & PR0002.

The AM0376 is an elliptical windscreen for use with GRAS Sound Intensity Probe 50GI.

The RA0001 is a right-angled adapter for using a 1/2" microphone with a 1/4" preamplifier. It can be used with any standard 1/2" microphone and 1/4" preamplifier such as the GRAS 26AC. The RA0001 could be useful in situations where the microphone has to be flush mounted on a wall.

The GRAS RA0003 is a straight adapter, for placing between a 1/2" microphone and a 1/4" preamplifier.

The RA0006 is a right-angled adapter for using a 1/4" microphone with a 1/4" preamplifier. It can be used with any standard 1/4" microphone and 1/4" preamplifier such as the GRAS 26AC. The RA0006 could be useful in situations where the microphone has to be flush mounted on a wall.

Recommendation: Choose a microphone with low sensitivity instead of using the RA0016.The RA0016 is a 20 dB attenuator for inserting between a 1/2" microphone and preamplifier. It will attenuate the output signal of the microphone by 20 dB in order to avoid overloading the preamplifier. The RA0016 is useful when measuring very high sound pressure levels using a preamplifier with limited dynamic range.  The RA0016 will work properly only with externally polarized microphones. For prepolarized microphones, use the RA0018.

The RA0017 is a simple adapter for using a 1" microphone with a 1/2" preamplifier. It can be used with any standard 1" microphone and 1/2" preamplifier such as the GRAS 26AK.

Recommendation: Choose a microphone with low sensitivity instead of using the RA0018.RA0018 is a 20 dB attenuator for inserting between a 1/2" prepolarized microphone and preamplifier. It will attenuate the output signal of the microphone by 20 dB in order to avoid overloading of the preamplifier. The RA0018 is useful when measuring very high sound pressure levels using a preamplifier with limited dynamic range.The RA0018 will work properly only with prepolarized microphones. For externally-polarized microphones, use the RA0016.

The RA0019 is an adapter for using a 1/4" microphone with a 1/2" preamplifier. Its influence on the acoustic field is minimal. To reduce attenuation of the microphone signal, the guard ring of the preamplifier is extended through the RA0019.

The RA0020 is specially designed and optimized for use with 1/2" microphones for sound pressure measurements, when high speed wind comes from one known direction e.g. in a wind tunnel.

RA0020-A is a nosecone for 1/2" microphones. It is similar to RA0020 but made of aluminium for lightness.

The RA0022 is specially designed and optimized for use with 1/4" microphones for sound pressure measurements, when high speed wind comes from one known direction e.g. in a wind tunnel.

The RA0063 is an adapter for using a 1/8" microphone with a 1/4" preamplifier. It can be used with any standard 1/8" microphone and 1/4" preamplifier such as the GRAS 26AC.

The GRAS RA0067 enables a prepolarized 1/2" microphone (typically a GRAS 40AD) to be used as a high-impedance sound source.

The RA0073 is an adapter for using a 1˝ microphone with a ½˝ preamplifier.The influence of the RA0073 on the acoustic field is minimal.

The GRAS RA0077 adapts a 1/2” microphone (remove grid) into a 1" microphone (without grid). Designed for NBS 9A / IEC 60313 Coupler GRAS RA0075 and Artificial Ear with NBS Coupler GRAS 43AF.

Pliers for firm but gentle gripping of a 1/2” microphone when unscrewing its protection grid or unscrewing the microphone from a preamplifier.

The GRAS RA0082 is an adapter for using a 1/8" microphone with a 1/4" preamplifier.

The GRAS RA0086 is similar to the GRAS RA0067 but is used with a 1/4" externally polarised microphone (typically a GRAS 40BP) which can then be used as a high-impedance sound source, e.g. when calibrating an acoustic coupler such as the GRAS RA0045. The RA0086 has a microdot connector.

For avoiding ground loops, e.g. with GRAS RA0085 Insulated coupling for artificial ear in telephone testing set-ups using the GRAS 43AD Artificial Ear.

Cap for rain protection of GRAS array microphones GRAS 40PR and 40PQ. It also fits QC microphones 40PP and 40PK.

  For use when humidity levels are high and only with a rear-vented 1” microphone. An indicator placed on the side of the dehumidifier shows when it needs to be dried out before further use. In the case of the GRAS 40EH 1” Microphone used in the GRAS 40HF Low-noise Level Microphone System, please order only at the time of ordering a GRAS 40HF.  

For use with GRAS RA0113 2cc Coupler.

The RA0117 is an adapter for mounting a 1/4" microphone in couplers designed for 1/2" microphones.

Recommendation: Choose a microphone with low sensitivity instead of using the RA0118. The RA0118 is an attenuator for inserting between a 1/4" microphone and preamplifier. It attenuates the output signal of the microphone by approximately 16 dB in order to avoid overloading the preamplifier or following analyzer. The RA0118 is useful when measuring very high sound pressure levels using a preamplifier or analyzer with limited dynamic range.

For use with 1/2” Free-field microphones when measuring noise according to ANSI requirements.

The RA0127 is a rain protection cap for use with 1/4" microphones.

The GRAS RA0131 is a rain protection cap for use with 1/2" microphones.

For use when humidity levels are high and only with a rear-vented 1/2” microphone.An indicator placed on the side of the dehumidifier shows when it needs to be dried out before further use.

The RA0173 is specially designed and optimized for use with 1/8" microphones for sound pressure measurements, when high speed wind comes from one known direction e.g. in a wind tunnel.

The RA0190 is a right-angled adapter for using a 1/2" microphone with a 1/2" preamplifier. It can be used with any standard 1/2" microphone and 1/2" preamplifier. The RA0190 could be useful in situations where the microphone has to be flush mounted on a wall.

GRAS RA0302 is a removal tool for 1/2" and 1/4" flush-mount microphones.