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Sound and Vibration Instrument Hire and Calibration

Measurement Microphones


 

Condenser microphone are widely used in noise measurements because they offer the best linearity, frequency range and high stability. All the measurement microphones we supply conform to BS EN 61094 and are mechanically similar.

Precision Measurement Microphones

For example the B&K 4165, CEL 192-2F, GRAS 40AF and Nor 1220 have similar mechanical and acoustical specifications and are therefore inter-changeable.

However some microphones are the pre-polarized, electret type and others, the air condenser type requiring a polarisation voltage **.

All our meters, microphones, accelerometers etc., are delivered with current calibration certificates, traceable to UKAS and our ISO 9001 laboratory is audited by British Standards - so we also offer a Microphone Calibration Service for everyone.

Measurement Microphones are very delicate and should be treated accordingly. The protection grid should not, normally, be removed as the slightest 'touch' can rupture the diaphragm, which is only a few microns thick. They are also susceptible to damp so outdoor systems like the B&K UA 1404 or GRAS 41AL systems are recommended for all outside applications. So please take care as any damage must be charged for and often means a replacement microphone. We also have a basic introduction to Measurement Microphones.

Measurement Microphones, Outdoor Microphones, Sound Intensity, Preamplifiers, Supplies etc.

 

Bruel & Kjaer Measurement Microphones


Type Diameter Sensitivity Frequency Voltage Response Daily Hire *
4133 ¹ 1/2" Ø 12.5 mV/Pa     4 Hz to 40 kHz 200V   Free field   £ 4
4134 ¹ 1/2" Ø 12.5 mV/Pa     4 Hz to 20 kHz 200V   Pressure £ 4
4135 * 1/4" Ø 4 mV/Pa     4 Hz to 100 kHz 200V   Free field £ 6
4136 * 1/4" Ø 1.6 mV/Pa     4 Hz to 70 kHz 200V   Pressure £ 6
4155 ² 1/2" Ø 50 mV/Pa     4 Hz to 16 kHz     0V   Free field £ 4
4165 ¹ 1/2" Ø 50 mV/Pa     3 Hz to 20 kHz 200V   Free field £ 4
4176 ² 1/2" Ø 50 mV/Pa     7 Hz to 12 kHz     0V   Free field £ 4
4188 1/2" Ø 32 mV/Pa     8 Hz to 12 kHz     0V   Free field £ 4
4189 ² 1/2" Ø 50 mV/Pa     6 Hz to 20 kHz     0V   Free field £ 4
4190 ¹ 1/2" Ø 50 mV/Pa     6 Hz to 20 kHz 200V   Free field £ 4

Casella CEL Measurement Microphones


Type Diameter Sensitivity Frequency Voltage Response Daily Hire *
  192 ¹ 1/2" Ø   50 mV/Pa     4 Hz to 16 kHz   200 V   Free field £   4

GRAS Measurement Microphones


Type Diameter Sensitivity Frequency Voltage Response Daily Hire *
  40AE ² 1/2" Ø   50 mV/Pa   4 Hz to 20 kHz     0 V   Free field £ 4
  40AF ¹ 1/2" Ø   50 mV/Pa   4 Hz to 20 kHz 200 V   Free field £ 4
  40AG 1/2" Ø   12.5 mV/Pa   3 Hz to 20 kHz 200 V   Free field £ 4
  40AN 1/2" Ø   50 mV/Pa   1 Hz to 10 kHz 200 V   Free field £ 4
  40AS ³ 1/2" Ø   40 mV/Pa   6 Hz to 16 kHz 200 V   Free, 90° £ 4
  40BF * 1/4" Ø     4 mV/Pa 10 Hz to 100 kHz 200 V   Free field £ 6

Norsonic Measurement Microphones


Type Diameter Sensitivity Frequency Voltage Response Daily Hire *
  1220 ¹ 1/2" Ø   50 mV/Pa     4 Hz to 16 kHz   200 V   Free field £ 4
  1225 ¹ 1/2" Ø   50 mV/Pa     4 Hz to 16 kHz 200 V   Free field £ 4
 

Note ¹ - these air condenser microphones are electrically, acoustically and mechanically compatible.
Note ² - these pre-polarized microphones are also interchangeable.
Note ³ - for use with outdoor microphones which are vertically aligned so sound source is at 90°.

* Sound level measurements up to 165 dB may be made with the B&K 4135 and the GRAS 40BF microphones, the B&K 4135 and GRAS 40BF prices include a 1/4" to 1/2" preamplifier adaptor and a 1/4" calibration coupler.

**  Pre-polarized electret may be used in place of air condenser types if the 200 V polarization voltage can be switched off.

Standard microphones may also be used to measure extremely low sound pressure levels. To download the application note right click here and select 'Save ......'.

 
B&K 3593 : Sound Intensity Probe  
 
Bruel & Kjaer Sound Intensity Probe

The B&K 3595 has been withdrawn, this information is for reference purposes only.

The 3595 is a two-microphone probe kit for measuring Sound Intensity.

Designed for use with 2260E Hand-held Sound Intensity System, the probe set includes the 1/2" Sound Intensity Microphone Pair Type 4197 enabling 1/3-octave centre frequency measurements, more details

 
GRAS 50AI : Sound Intensity Probe  
 
GRAS Sound Intensity Probe

GRAS 50AI has been withdrawn, the following information is for reference purposes only.

The GRAS sound intensity probe is durable and easy to use probe that fully complies with the
requirements of IEC 1043 for Class 1 sound intensity probes.

The sound intensity probe includes a set of 1/2" intensity microphones type 40AI, with spacers,
adaptors, preamplifiers and a remote control handle to control the complete data acquisition
process from the probe handle, when used with a Nor 840 analyser, .. more details

 
GRAS 40AK : Sound Intensity Microphone Pair £ 12 a day *
 
GRAS Sound Intensity Microphones

The GRAS sound intensity microphone sets includes two phase matched 1/2" intensity microphones,
spacers and 1/4" preamplifier adaptors.

The microphones have a free field response optimised for use in face to face configuration intensity
probes and have high sensitivity to enable low level measurements, more details

B&K UA 1404 : Outdoor Microphone Kit £ 7 a day *
 
Bruel & Kjaer Outdoor Microphone

For use with the B&K range of environmental noise analysers.

The Bruel & Kjaer Environmental microphone system fits over the standard microphone

It uses an incidence corrector to compensate for the now vertically aligned microphone and includes a rain cover to protect the diaphragm

B&K UA 1404 details


GRAS 41AL : Outdoor Microphone System £ 8 a day *
 
GRAS Outdoor Microphone

The GRAS Outdoor Microphone is designed to maintain a microphone's specifications when fitted with a rain cover, windshield and mounted vertically .

The kit includes a 3 m preamplifier cable with a Lemo 1B connector, a desiccator unit and a coupler with correction values for a range of calibrators.

GRAS 41AL details

 

Ideally suited for the Norsonic range of environmental noise analysers.


GRAS : Microphone Preamplifiers Daily Hire *
 
26AA : 1/4" with 0.3 m thin lead to Lemo 0B connector: GRAS 50AI sound intensity probe £   3
26AB : 1/4" with 1/2 " adaptor and integral Lemo 1B connector £   3
26AC : 1/4" with 2 m thin cable to Lemo 1B connector £   3
26AF : 1/2" with integral Lemo 1B connector - general purpose £   3
26AG : 1/2" with insert voltage connection, integral Lemo 1B £   3
26AK : 1/2" with integral Lemo 1B connector - general purpose £   3
 

Order preamplifier extension cables to suit your application. For more information on the GRAS preamplifiers click here

 
Nor 1201 : Norsonic Microphone Preamplifier £ 3 a day *
 
Norsonic Microphone Preamplifier

Norsonic 1/2" preamplifier with integral 1B connector - this is our general purpose preamplifier suitable for most applications.

It has a very low self noise level. Its high input impedance ensures a good low frequency response and the output stage is designed to drive long cables with full frequency range, more details.

There are a range of standard extension cable available including flat tape types to pass under doors etc.

 
GRAS 12AA : Microphone Power Supply / Signal Conditioner - dual channel £ 5 a day *
 
GRAS Microphone Power Supply

Dual channel, battery operated power supply for GRAS, Norsonic and other compatible preamplifiers with Lemo 1B 7-pin connectors.

Also useful with GRAS 41AL outdoor microphone systems when the sound level meter to be used does not have Lemo preamplifier inputs and / or polarisation voltage supplies.

High Pass filters, selectable gain, BNC outputs

GRAS 12AA Microphone Power Supply - details

 
Nor 335 : Norsonic Microphone Power Supply - 8 channels with signal conditioning £ 19 a day *
 
Norsonic Microphone Power Supply - 8 channels

Microphone and preamplifier power supplies with 200 V or 0 V polarisation voltage and signal conditioning for each channel - battery operated.

Ideal for use with multi-channel analysers and data capture systems - shown here with an 8-channel DAT recorder.

Nor 335 Microphone Power Supply - details

 
Nor 336 : Norsonic Microphone Power Supply - dual channel with signal conditioning £ 6 a day *
 
Norsonic Microphone Power Supply - dual channels

Battery operated, dual channel microphone power supply, preamplifier system.

Often used as a 'remote' microphone system enabling long cables back to the analyser.

Other applications include using as a Front-end for DAT recorders and similar data capture/analysis systems.

Mechanically compatible with the Sony D7 and D8 DAT Recorders

Nor 336 Microphone Power Supply - details

* Our standard hire charges are based on a 4-day minimum period, details other options