GRAS 50GI CCP Intensity Probe
Freq range: Ref. IEC 61043 Class 1
Dyn range: 27 dB(A) to 146
Sensitivity: 12.5 mV/Pa
GRAS 50GI is a sound intensity probe for direct connection to signal analyzers or data acqusition devices with IEPE inputs. The probe includes a pair of phase-matched prepolarized precision microphones which meet the requirements in IEC standard 61043 for a class-1 intensity probe. The small rugged 1/4" CCP preamplifiers ensure minimum disturbances to the sound field for accurate measurements in the full frequency range.
Technology
Typical applications and use
- Sound intensity measurements
- Sound source location
- Sound power measurements
- IEC 61043 standard measurements
- Sound source ranking
- Sound intensity mapping
Design
The probe set includes solid interchangeable spacers for microphone separations from 12 mm to 100 mm so that the probe can cover the frequency range from 50 Hz to 10 kHz.
All components are made specifically for sound intensity applications. Each small 1/4" diameter by 40 mm long microphone preamplifier is housed in a robust stainless steel casing, which enables novel probe designs for reducing disturbances to the soundfield otherwise brought about by the effects of shadows and diffraction, and a symmetry which enables reliable calibrations as described in the proposed standard (ISO/DIS 9614-2) for sound power measurements using sound intensity measurements.
The CCP Intensity Probe GRAS 50GI comprises 40GK sound Intensity Microphone Pair, two 26CB CCP Microphone Preamplifiers, four solid spacers of various lengths, windscreen, and probe handle.
The Type 50GI is delivered in a carrying case as a ready-to-use kit, complete with all the above accessories.
The microphones are 1/2/ free-field prepolarized microphones with a uniquely-designed pressure equalisation system which ensures extremely well defined phase characteristics.
The microphones and preamplifiers are mounted on a swivel head on the telescopic arm of the handle. To cover the full frequency range from 50 Hz to 10 kHz, the 50GI probe is delivered with four solid spacers for spacing the microphones at 12 mm, 25 mm, 50 mm and 100 mm. These spacers can be easily interchanged without dismantling the probe.
Specifications
Frequency ranges for different microphone spacers
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.
Ordering info
Included items
GRAS 40GK | 1/2" Prepolarized Intensity Microphone Kit |
GRAS 26CB Set | 1/4" CCP Standard Preamplifier with Microdot connector |
GRAS AA0070 | 3 m Microdot - BNC cable |
GRAS AI0044 | Probe handle |
GRAS AI0001 | Windscreen for Intensity Probes |
Optional accessories
GRAS 12AQ | 2-Channel Universal Power Module with signal conditioning and PC interface |
GRAS 42AP | Intelligent Pistonphone, Class 0 |
GRAS 51AB | Phase Calibrator according to IEC 61043 |
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.