Sound Intensity calibration simplified by new Calibrator.
Sound and vibration specialist, Brüel & Kjaer UK has launched
a new calibrator that enables accurate on-site calibration of
sound intensity measuring instruments without having to
dismantle the sound intensity probe.
The new calibrator Type 4297 is designed to eliminate the need for
dismantling the sound intensity probe and is optimised for use with
B&K's 2260E InvestigatorTM sound intensity system for phase
enhancement. As there is no longer any need to dismantle the probe,
the risk of misplacing the spacer is now eliminated.
A complete sound intensity calibrator in one compact portable unit
with built-in sine and broadband sound sources, Type 4297 can also
be used with sound intensity analysis systems based on PULSE.
Type 4297 is ideal for on-site sound pressure calibration (at 251.2Hz,
Type 1 IEC 60942) and pressure residual intensity index verification
of a wide range of B&K sound intensity probes. These include Types
3583, 3584, 3595 and 3599 with sound intensity microphone pair
Type 4197 as well as earlier Types 3545 or 3548 with sound intensity
microphone pair Type 4181. The microphones must be calibrated with
1/4-inch preamplifiers and a 12mm spacer.
For calibration of sound pressure sensitivity, the microphones are
both positioned in the calibration chamber and are thus exposed to
exactly the same sound pressure (amplitude and phase).
The broadband sound source is provided for measurement of the
pressure-residual intensity index spectrum and this is also used to
assess the accuracy of sound intensity measurements. A calibration
chart is supplied that states the levels that should be detected during
calibration. The acoustic feedback system automatically adjusts for
variations in atmospheric pressure and makes the requirement for a
barometer for correction purposes superfluous.
Type 4297 fulfils the requirements of IEC 61043, Electroacoustics
- Instruments for the Measurement of Sound Intensity - Measurements
with Pairs of Pressure Sensing Microphones: 1993, and is housed in
a compact case measuring 60 x 55 x 170mm and weighing 730 grams.
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