New High Level, High Frequency Microphone.
Sound and vibration specialist, Bruel & Kjaer has launched
a new prepolarised pressure-field ¼" microphone for
high-level and high-frequency measurements.
Type 4944 is manufactured from new materials and assembled with
a new method for mounting the diaphragm that enables the microphone
to withstand rough handling. As a pressure-field device, Type 4944 is
designed for use in confined spaces and small cavities, close to hard
reflective surfaces or f lush-mounting. Type 4944 can also be used
with sound level meters to measure high soi~ñd pressure levels.
Specifications include sensitivity of 1.0mV/Pa, frequency range from
4Hz to 70kHz, dynamic range from 30 to l70dB(A) and temperature
range from -40 to +150°C. Sensitivity is optimised to allow measurement
of high sound pressure levels without clipping in the DeltaTron
The shape of the Type 4944's front delivers excellent microphone
performance when flush-mounted while the laser welded diaphragm
on the microphone housing ensures that the sensitivity is resistant
to rough handling during mounting. The overall robustness of the
4944 makes it capable of withstanding the IEC 68-2-32 one metre
drop. Clean room assembly of the microphone allows Type 4944
to be used in high-humidity environments and still produce reliable
Each Type 4944 microphone is supplied complete with a disk that
carries all individual calibration data along with randomincidence
and pressure field corrections. The influence of the ¼" nose cone
(UA 0385) is also available on the disk.
The new 4944 pressure-field microphone complements Bruel &
Kjaer's wide range of specialist microphones for noise and sound
applications. These include the latest in the Falcon range: 4942
and 4943 for diffuse-field applications. Offering a direct replacement
for the traditional Brüel & Kjaer Type 4166, the new 4943 is a ½"
diffuse-field microphone offering sensitivity of 50mV/Pa, frequency
range from 4Hz to 10kHz, dynamic range from l6dB(A) to 148dB
and temperature range from -40 to +300°C.
Type 4942 is a pre-polarised ½" dedicated diffuse-field microphone
optimised to measure over an extended frequency range from
3Hz to 14kHz with dynamic range from 14.6dB(A) to 146dB
and operating temperature range from -40 to +150°C.
For more information, please contact :-
Bruel & Kjaer, Bedford House, Rutherford, Close,
Stevenage, Hertfordshire, SG1 2ND. UK
Tel: +44(0) 1438 739000, Fax: +44(0) 1438 739099
Web site: www.bksv.com