GRAS 46BC 1/4" CCP Multifield Microphone Set, High Sensitivity
Use our chat for personal support. Or contact us via +45 31 33 18 19 or salg@GOmeasure.dk
- Only multifield microphone on the market.
- Optimized for Free-field measurement.
- Lowest ¼″ noise floor.
- Reduced influence of the angle of incidence.
- Meets the requirements of the AES Acoustics Measurements recommendation.
- Well-suited for high-frequency measurements.
- Reduced influence on measurement environment due to their small size.
Discover the possibilities
More information
Description
Acoustic challenges in a car cabin
The constant evolution of motor vehicles is a never-ending source of new acoustic challenges. The transition from internal combustion engines (ICEs) to electric vehicles (EVs) is a lot more than just swapping power sources.
New challenges
Added to the vehicle noise itself come the audio and infotainment system assessment challenges. Efforts to increase efficiency and extend the range between charging go beyond the technological improvements in battery and motor efficiency. Lighter materials are being incorporated into the vehicle structures and interiors. This introduces a range of new challenges for assessing the quality of in-cabin audio:
- Lighter materials with their own dampening characteristics
- Highly reflective elements like instrumentation panels, windows, and even panoramic glass that may or may not be exposed on the interior ceiling.
- The combination of the above.
This results in a combination of sound fields where noise can come to the occupants from multiple angles, with a range of dampening effects for different frequencies. If not evaluated properly, occupants could experience muddled audio for some frequencies or reverberant dissonance for other frequencies.
Beyond the capability of traditional testing
The new challenges have pushed audio testing needs beyond the capabilities of ½″ microphones.
Can the 46BC match ½″ microphones on the low end?
The noise floor of traditional ¼″ microphones was once a primary limitation for use in automotive NVH testing. However, the 46BC has the lowest noise floor of any ¼″ microphone on the market, making it uniquely suited to replace the ½″ microphones in current use, enabling improved high-frequency accuracy, while maintaining low noise floors.
Benefits of 46BC at a glance:
- Only multifield microphone on the market.
- Optimized for Free-field measurement.
- Lowest ¼″ noise floor.
- Reduced influence of the angle of incidence.
- Meets the requirements of the AES Acoustics Measurements recommendation.
- Well-suited for high-frequency measurements.
- Reduced influence on measurement environment due to their small size.
Why is a ¼″ microphone better?
The actual physical size of ¼″ microphones provides many benefits for in-cabin acoustic testing. The size-related properties (blog post) reduce the pressure build-up effect on the diaphragm and minimizes error when measuring in a non-free-field environment, such as in-cabin. This enables improved accuracy at higher-frequency ranges. And when accounting for real-world conditions and measuring where there are many reflections and disturbances, such as in-cabin, the physical advantages of a ¼″ microphone can greatly increase accuracy and simplify post-processing data
The cabin is a complex sound field, consisting of multiple source contributions that can change due to factors that depend on velocity, such as road noise, wind noise, braking noise, etc. This environment is a prime example of a multifield environment, and it can only be measured accurately with ¼″ or smaller microphones.
According to the Acoustic Engineer Society (AES) In-car Acoustics Measurements recommendation, microphones that match the characteristics of 46BL-1 and the 46BC are ideally suited for these types of measurements.
Freq range: 4 Hz to 20 kHz
Dyn range: 24 dB(A) to 145 dB
Sensitivity: 20 mV/Pa
The 46BC is a high-sensitivity, low-noise, multifield ¼″ CCP condenser microphone set with rear venting and is optimized for use with the protection grid.
Documents
Options
Video
Acoustic challenges in a car cabin
The constant evolution of motor vehicles is a never-ending source of new acoustic challenges. The transition from internal combustion engines (ICEs) to electric vehicles (EVs) is a lot more than just swapping power sources.
New challenges
Added to the vehicle noise itself come the audio and infotainment system assessment challenges. Efforts to increase efficiency and extend the range between charging go beyond the technological improvements in battery and motor efficiency. Lighter materials are being incorporated into the vehicle structures and interiors. This introduces a range of new challenges for assessing the quality of in-cabin audio:
- Lighter materials with their own dampening characteristics
- Highly reflective elements like instrumentation panels, windows, and even panoramic glass that may or may not be exposed on the interior ceiling.
- The combination of the above.
This results in a combination of sound fields where noise can come to the occupants from multiple angles, with a range of dampening effects for different frequencies. If not evaluated properly, occupants could experience muddled audio for some frequencies or reverberant dissonance for other frequencies.
Beyond the capability of traditional testing
The new challenges have pushed audio testing needs beyond the capabilities of ½″ microphones.
Can the 46BC match ½″ microphones on the low end?
The noise floor of traditional ¼″ microphones was once a primary limitation for use in automotive NVH testing. However, the 46BC has the lowest noise floor of any ¼″ microphone on the market, making it uniquely suited to replace the ½″ microphones in current use, enabling improved high-frequency accuracy, while maintaining low noise floors.
Benefits of 46BC at a glance:
- Only multifield microphone on the market.
- Optimized for Free-field measurement.
- Lowest ¼″ noise floor.
- Reduced influence of the angle of incidence.
- Meets the requirements of the AES Acoustics Measurements recommendation.
- Well-suited for high-frequency measurements.
- Reduced influence on measurement environment due to their small size.
Why is a ¼″ microphone better?
The actual physical size of ¼″ microphones provides many benefits for in-cabin acoustic testing. The size-related properties (blog post) reduce the pressure build-up effect on the diaphragm and minimizes error when measuring in a non-free-field environment, such as in-cabin. This enables improved accuracy at higher-frequency ranges. And when accounting for real-world conditions and measuring where there are many reflections and disturbances, such as in-cabin, the physical advantages of a ¼″ microphone can greatly increase accuracy and simplify post-processing data
The cabin is a complex sound field, consisting of multiple source contributions that can change due to factors that depend on velocity, such as road noise, wind noise, braking noise, etc. This environment is a prime example of a multifield environment, and it can only be measured accurately with ¼″ or smaller microphones.
According to the Acoustic Engineer Society (AES) In-car Acoustics Measurements recommendation, microphones that match the characteristics of 46BL-1 and the 46BC are ideally suited for these types of measurements.
Freq range: 4 Hz to 20 kHz
Dyn range: 24 dB(A) to 145 dB
Sensitivity: 20 mV/Pa
The 46BC is a high-sensitivity, low-noise, multifield ¼″ CCP condenser microphone set with rear venting and is optimized for use with the protection grid.