G.R.A.S. 46BP 1/4" LEMO Pressure Standard Microphone Set

Freq range: 4 Hz to 70 kHz
Dyn range: 39 dB(A) to 169 dB
Sensitivity: 1.5 mV/Pa
  • 46BP 1/4

Introduction

The 46BP is a ¼" LEMO microphone set for pressure measurements. Read about the CCP equivalent [46BD].

The set consists of the ¼" random-incidence microphone 40BP and the ¼" preamplifier 26TC with a 3 m integrated cable with a 7-pin LEMO connector.

This combination was chosen to save you time and give you the best possible properties and reliability in the microphone and preamplifier match. Your workflow is optimized and typical handling errors are minimized.

Not only have we made a set of the best possible combination of microphone and preamplifier, we have also included TEDS, the Transducer Electronic Data Sheet standard according to IEEE-1451.4. Multi-channel users appreciate having an intelligent transducer, like 46BP, that can supply properties, types, and calibration data directly to measurement platforms that support TEDS.

46BP is individually factory-calibrated and delivered with a calibration chart stating its specific open-circuit sensitivity and pressure frequency response.

Typical applications and use

46BP is typically used for sound pressure, high frequency, and high level pressure measurements. It is suitable for general purpose acoustic measurements in couplers and at boundaries.

The microphone in the 46BP is very versatile when connected to the RA0086 Transmitter Adapter for ¼" Microphones. The 46BP becomes a high-impedance sound source when the RA0086 takes a calibration signal directly from the signal generator and makes the microphone behave like an electrostatic loudspeaker. When used for calibrating an acoustic coupler, this gives a frequency response that is as good as when the 46BP behaves like a microphone.

Compatibility

The 46BP uses a 7-pin LEMO connector, which requires an input module that supports this technology.

For more information, see System Setup.

System verification

For daily verification and check of your measurement setup, we recommend using a calibrator like G.R.A.S. Sound Level Calibrator 42AB

For proper sensitivity calibration, we recommend using a pistonphone like G.R.A.S. Intelligent Pistonphone 42AP

Quality and warranty

All G.R.A.S. microphone sets are made of high-quality materials that will ensure life-long stability and robustness. The microphone sets are all assembled in verified clean-room environments by skilled and dedicated operators with many years of expertise in this field.

The microphone diaphragm, body, and improved protection grid are made of high-grade stainless steel, which makes the microphone resistant to physical damage, as well as corrosion caused by aggressive air or gasses.

This, combined with the reinforced gold-plated microphone terminal which guarantees a highly reliable connection, enables G.R.A.S. to offer 5 years warranty against defective materials and workmanship.

Learn more about G.R.A.S.' unique warranty policies.

Service

If you accidentally damage the diaphragm on a G.R.A.S. microphone, we can—in most cases—replace it at a very reasonable cost and with a short turn-around time. This not only protects your investment, but also pleases your quality assurance department because you don't have to worry about new serial numbers, etc.

Learn more about G.R.A.S.' service program.

Calibration

Before leaving the factory, all G.R.A.S. microphone sets are calibrated as a unit in a controlled laboratory environment using traceable calibration equipment. The sets are delivered with calibration charts including sensitivity values and frequency response graphs for the complete set. You can use the sensitivity value directly in your system setup.

Depending on the use, measurement environment, and internal quality control programs, we recommend recalibrating the microphone set at least every second year.

Learn more about G.R.A.S.' calibration services.

TYPE (Microphone features) P
Frequency range (±1 dB) Hz 10 to 25 k
Frequency range (±2 dB) Hz 4 to 70 k
Dynamic range lower limit with G.R.A.S. preamplifier dB(A) 39
Dynamic range upper limit with G.R.A.S. preamplifier @ +28 V / ±14 V power supply dB 169
Dynamic range upper limit with G.R.A.S. preamplifier @ +120 V / ±60 V power supply dB 169
Set sensitivity @ 250 Hz (±3 dB) mV/Pa 1.5
Set sensitivity @ 250 Hz (±3 dB) dB re 1V/Pa -56.5
Output impedance Ω 75
Power supply min. to max. (single/balanced) V 28 to 120 / ± 14 to ± 60
DC-offset, min., single suppy V 0.5 x Vs - 1
DC-offset, max., single suppy V 0.5 x Vs + 4
DC-offset, balanced supply V -1 to 4
Microphone venting Rear/Front
IEC 61094-4 Compliance WS3P
Temperature range, operation °C / °F -30 to 70 / -22 to 158
Temperature range, storage °C / °F -40 to 85 / -40 to 185
Temperature coefficient @250 Hz dB/°C / dB/°F -0.01 / -0.006
Static pressure coefficient @250 Hz dB/kPa -0.008
Humidity range non condensing % RH 0 to 100
Humidity coefficient @250 Hz dB/% RH -0.0013
Influence of axial vibration @1 m/s² dB re 20 µPa 55
TEDS UTID (IEEE 1451.4 ) 27 v. 1.0
Connector type 7-pin LEMO (FGG.1B.307)
CE/RoHS compliant/WEEE registered Yes / Yes/Yes
Weight g / oz 10 / 0.353

Typical frequency response (without protection grid).

Optional items

G.R.A.S. 42AA

Pistonphone, Class 1

G.R.A.S. 42AP

Intelligent Pistonphone, Class 0

G.R.A.S. 12AA

2-Channel LEMO Power Module with gain, filters and Syscheck generator

G.R.A.S. 12AK

1-Channel Power Module with gain, filters and SysCheck generator

G.R.A.S. 12AQ

2-Channel Universal Power Module with signal conditioning and PC interface