BRUEL & KJAER 4184-A Guide

Technical
Documentation
Weatherproof Microphone Unit Type 4184-A
for Hand-held Analyzer
Types 2250, 2250-L and 2270
Supplement to Instruction Manual BE1712
HEADQUARTERS: Brüel&Kjær Sound & Vibration Measurement A/S · DK-2850 Nærum · Denmark
Telephone: [phone] · Fax: [phone] · www.bksv.com · [e-mail]
Local representatives and service organisations worldwide
ËBE-1843---,Î
English BE1843–12

BE184312 March 2012
Weatherproof Microphone Unit
Type 4184-A
for Hand-held Analyzer
Types 2250, 2250-L and 2270
Type 2250, from Hardware Version 1.1
Type 2250-L, from Hardware Version 2.0
Type 2270, from Hardware Version 3.0
Supplement to Instruction Manual
BE 1712

Copyright 2006 – 2012, Brüel & Kjær Sound & Vibration Measurement A/S
All rights reserved. No part of this publication may be reproduced or distributed in any form, or by any means,
without prior written consent from Brüel & Kjær Sound & Vibration Measurement A/S, Nærum, Denmark.
Safety Considerations
This apparatus has been designed and tested in accordance with IEC61010 –1 and EN61010– 1 Safety Require-
ments for Electrical Equipment for Measurement, Control and Laboratory Use. This manual contains infor-
mation and warnings which must be followed to ensure safe operation and to retain the apparatus in safe condition.
Special note should be made of the following:
Safety Symbols
The apparatus will be marked with this symbol when it is important that you refer to the associated warning
statements given in the manual.
Protective Earth Terminal Hazardous Voltage
Explosion Hazard
The equipment is not designed to be used in potentially explosive environments. It should not be operated in the
presence of flammable liquids or gases.
Warnings
• Switch off all power to equipment before connecting or disconnecting their digital interface. Failure to do so
could damage the equipment.
• Whenever it is likely that the correct function or operating safety of the apparatus has been impaired, it must
be made inoperative and be secured against unintended operation.
• Any adjustment, maintenance and repair of the open apparatus under voltage must be avoided as far as possible
and, if unavoidable, must be carried out only by trained service personnel.
• Do not dispose of electronic equipment or batteries as unsorted municipal waste
• It is your responsibility to contribute to a clean and healthy environment by using
the appropriate local return and collection systems
• Hazardous substances in electronic equipment or batteries may have detrimental
effects on the environment and human health
• The symbol shown to the left indicates that separate collection systems must be used
for any discarded equipment or batteries marked with that symbol
• Waste electrical and electronic equipment or batteries may be returned to your
local Brüel & Kjær representative or to Brüel & Kjær Headquarters for disposal

Table of Contents
CHAPTER 1
Introduction.......................................................................................................................................... 1
1.1 About This Supplement............................................................................................................................. 1
1.2 System Overview....................................................................................................................................... 1
CHAPTER 2
Information Required by the Standards ............................................................................................ 3
2.1 Introduction................................................................................................................................................ 3
2.2 Mounting and Placing the Microphone...................................................................................................... 3
2.4 Calibration ................................................................................................................................................. 4
2.7 Measuring at Low Static Pressure............................................................................................................. 4
CHAPTER 3
Conformance Testing.......................................................................................................................... 5
3.1 Introduction................................................................................................................................................ 5
3.2 Mounting for Acoustical Tests ................................................................................................................... 5
3.3 Periodic Testing of Acoustical Frequency Responses .............................................................................. 5
3.4 Mounting for Mechanical Vibrations Tests................................................................................................. 5
3.5 Electrical Substitute for Microphones........................................................................................................ 6
CHAPTER 4
Specifications ...................................................................................................................................... 7
4.1 Specifications ............................................................................................................................................ 7
4.4 Reference Conditions for Acoustic Calibration.......................................................................................... 7
4.5 Microphone................................................................................................................................................ 7
4.7 Directional Responses............................................................................................................................. 10
4.8 Self-generated Noise............................................................................................................................... 13
4.9 Measuring Ranges .................................................................................................................................. 17
APPENDIX A
Tables ................................................................................................................................................. 23
A.2 Free-field Frequency Responses ............................................................................................................ 23
A.3 Diffuse-field Frequency Responses......................................................................................................... 26
A.4 Free-field Frequency Responses for Diffuse-field Calibrated Instruments.............................................. 27
A.5 Directional Responses............................................................................................................................. 28
A.6 Periodic Testing of Acoustical Frequency Responses ............................................................................ 35
APPENDIX D
Using Microphone Type 4184-A ....................................................................................................... 37
D.1 Mount Pistonphone Type 4228 onto Type 4184-A.................................................................................. 37
D.2 Mount Multifunction Acoustic Calibrator Type 4226 onto Type 4184-A................................................... 38
D.3 Mount Electrical Substitute for Microphones on the Built–in Microphone Preamplifier ........................... 40
INDEX........................................................................................................................................................................... 43

1
Chapter 1
Introduction
1.1 About This Supplement
This document is a supplement, to Instruction Manual for Hand-held Analyzer Types 2250, 2250-L and
2270 BE 1712. It provides the information relevent when Hand-held Analyzer Type 2250, 2250 L or 2270
is configured with Weatherproof Microphone Unit Type 4184-A.
The combination of Weatherproof Microphone Unit Type 4184-A and the hand-held analyzer is intended
for outdoor use where a weatherproof microphone solution is needed.
The numbering of chapters, sections, figures and tables in this supplement corresponds to
Instruction Manual BE 1712. This supplement only contains content that is different from the
instruction manual and is specific to this microphone configuration. The other chapters, sections,
figures and tables should be read in Instruction Manual BE 1712.
Also see section 1.1 of the instruction manual.
1.2 System Overview
1.2.4 Hardware Setup
This section provides an overview of the additional hardware components used when the analyzers are
configured with Weatherproof Microphone Unit Type 4184-A. The other hardware components can be
found in Instruction Manual BE 1712, section 1.2.4.
NOTE:
• Only one Weatherproof Microphone Unit Type 4184-A can be connected to Type 2270
• Weatherproof Microphone Unit Type 4184-A is calibrated with Brüel & Kjær Pistonphone
Type 4228, which has a calibration frequency of 251.2 Hz and a calibration level of approximately
124 dB
• Weatherproof Microphone Unit Type 4184-A includes the Microphone Preamplifier Type ZE-0773
• Weatherproof Microphone Unit Type 4184-A is specified for two reference directions. In the user
interface they are selected as two different microphones and are called: 4184-A 0° (Top) and 4184-A
90° (Side)
– 4184-A 0° (Top)’s reference direction is defined as the inward direction toward the Microphone
Reference Point on the microphones rotational axis coming from the opposite direction of the
electrical output
– 4184-A 90° (Side)’s reference direction is defined as the inward direction toward the Microphone
Reference Point perpendicular to the microphones rotational axis
• Weatherproof Microphone Unit Type 4184-A has a built-in Windscreen and is therefore not specified
without the Windscreen

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE 17122
• Weatherproof Microphone Unit Type 4184-A cannot be mounted directly onto the analyzer. It is
always connected through an extension cable
• Weatherproof Microphone Unit Type 4184-A is not specified together with Outdoor Microphone Kit
UA-1404
Table 1.1
Additional
hardware
components
needed
for conformance
testing of
the analyzers
configured with
Type 4184-A
Quantity Brüel & Kjær Type/Part
Number Description
1 Type 4184-A Weatherproof Microphone Unit
1 WA-0302-C Electrical Substitute for Microphone cartridge, 18 pF
1 DB-4237 Fixture for WA-302-C
1 UA-1732 Fixture for calibration assembly
1 DB-4199 Calibration Adaptor
1 210411 Adapter for hose, EMC tests
1 Type 4228 Pistonphone

3
Chapter 2
Information Required by the Standards
2.1 Introduction
This chapter contains detailed information required by the standards to be described in the
Instruction Manual.
2.2 Mounting and Placing the Microphone
Weatherproof Microphone Unit Type 4184-A must be connected to the analyzer with Microphone Cable
AO-0697-D-100. The microphone cannot be mounted directly onto the analyzer.
Weatherproof Microphone Unit Type 4184-A is designed to operate mounted vertically with the bird
spikes pointing upwards. The microphone should not be mounted outdoors with other orientations.
Weatherproof Microphone Unit Type 4184-A can be mounted on a pipe with Pole Adapter DB-3068. The
adapter has a female thread that fits onto the male thread of standard 1.5opening diameter water pipes
(ISO 228-1 G1). The mounting ring of the microphone unit is screwed onto the pole adapter.
The microphone can also be mounted on a tripod with Tripod Adaptor UA-1112. The mounting ring of the
microphone unit is screwed onto the tripod adaptor.
The cable must be fed through the pipe or the hole in the tripod adaptor. Connect the cable to the
microphone, mount the microphone on the adaptor and secure it with the mounting ring.
The position of the sound opening of the microphone unit (the Microphone Reference Point) is 118 mm
above the bottom of the windscreen mounting thread.
The microphone must be placed away from shielding, reflecting, or absorbing objects. In a diffuse sound
field, absorbing objects will reduce the measured sound levels. In a free sound field, reflecting objects can
change the measured sound levels. Typically, the sound level 0.5 m from a plain reflecting wall is 3 dB
higher than if there was no wall.
The operator of the system may be personally shielding, absorbing, and reflecting, and the operator can
also be an additional noise source.
The optimum position for the microphone is best found by trying different positions and observing the
resulting sound levels.

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE 17124
2.4 Calibration
The procedures for calibrating the analyzer can be found in User Manual for Hand-held Analyzer
Types 2250 and 2270 BE 1713, User Manual for Hand-held Analyzer Type 2250-L BE 1766, and in
appendix D.1 of this manual.
Weatherproof Microphone Unit Type 4184-A should be calibrated with Brüel & Kjær Pistonphone
Type 4228. Type 4228 is a class LS calibrator as specified in International Standard IEC 60942, Electro-
acoustics Sound Calibrators. The nominal frequency and sound pressure level of Type 4228 are 251.2 Hz
and 124 dB re. 20 Pa, respectively. The sound pressure level in Type 4228 is proportional to the static
pressure; therefore, the procedure in the User Manual for Pistonphone Type 4228 BE 1094 for compen-
sating for the static pressure should be followed.
The procedure for the calibration necessary for the electrical tests during conformance testing can be
found in section 3.5.
While performing the calibration procedures, the analyzer is automatically checked for its ability to
perform the measurements.
2.7 Measuring at Low Static Pressure
The frequency response of the microphone depends on the static pressure. Using a sound level calibrator
to adjust the sensitivity of a Sound Level Meter at the calibration check frequency, 251.2 Hz, provides no
information on the influence of static pressure on frequency response.
Conformance to the specified standards ensures that the system measures within the standard’s tolerances,
in the range from 85 kPa to 108 kPa. In the range of 65 kPa to 108 kPa, the change of frequency response
relative to the response at 251.2 Hz will be less than 0.8 dB.
At the calibration check frequency, the microphone is rather insensitive to variations in the static pressure.
However, Pistonphone Type 4228 is sensitive to variations in the static pressure. Therefore, the procedure
in its manual for compensating for the static pressure should be followed, see section 2.4.

5
Chapter 3
Conformance Testing
3.1 Introduction
This chapter contains the information needed to conduct conformance testing according to the specified
standards.
3.2 Mounting for Acoustical Tests
For acoustical tests, it is important that the test rig for mounting the microphone to be tested is designed to
minimise the influence of reflections to a level that is comparatively smaller than the test parameter’s
maximum Expanded Uncertainties of Measurement. This has to be demonstrated with a good, known
laboratory microphone.
For Acoustical tests, Weatherproof Microphone Unit Type 4184-A should be mounted on a standard 1.5
water pipe, see section 2.2. The pipe must be of sufficient length, so as to avoid influence of reflections
from the mounting of the pipe in the test rig. The microphone must be connected to the analyzer with
Microphone Cable AO-0697-D-100.
3.3 Periodic Testing of Acoustical Frequency Responses
Acoustical signal test of frequency response can be made with plane progressive waves in an anechoic
facility. However, this is normally very time-consuming and difficult to do with sufficient accuracy. For
the purpose of periodic testing, it is recommended that you use the Brüel & Kjær Multifunction Acoustic
Calibrator Type 4226 for acoustic frequency response tests.
For instructions on how to mount the calibrator on the microphone, see appendix D.2.
The Multifunction Acoustic Calibrator must be set to its Calibration and Pressure sound field modes. The
calibrator must be calibrated. Further details can be found in the Multifunction Acoustic Calibrator
Instruction Manual (BE 1041).
Adjustment data, which must be applied to the sound levels displayed in response to the sound pressure
produced by Multifunction Acoustic Calibrator Type 4226 in order to obtain the equivalent sound levels
that would be displayed in response to plane progressive sinusoidal sound waves incident from the
reference direction, are given in Table A.49.
3.4 Mounting for Mechanical Vibrations Tests
Only Weatherproof Microphone Unit Type 4184-A contributes significantly to the sensitivity to mechanical
vibrations and the microphone cannot be mounted directly onto the analyzer. Therefore, only the
microphone needs to be tested.
Tripod Adaptor UA-1707 can be used for mounting the microphone on the shaker. Alternatively, the inner
M53 × 1.25 thread of the mounting ring of the microphone or pole adaptor DB-3068 can be used.

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE 17126
If, however, you want to test the analyzer, then use the Tripod Mounting Thread situated centrally on the
underside of the analyzer.
3.5 Electrical Substitute for Microphones
To obtain a BNC type electrical input, replace the microphone cartridge with a WA-0302-C, 18 pF, fitted
with a 10-32 UNF-to-BNC adaptor, UA-0245.
The microphone cartridge is an integrated part of the weather protection in Weatherproof Microphone
Unit Type 4184-A. For instructions on how to mount WA-0302-C on the preamplifier see appendix D.3.
This Electrical Substitute for Microphones has, together with the preamplifier; a nominal attenuation of
0.55 dB.
The electrical input obtained in this way has a maximum input level of minimum ±10.07 VPeak and no
damage will occur for signals up to ±20 VPeak.
All electrical inputs can be short-circuited when needed for test.
To calibrate the analyzer for the electrical conformances test with a calibration that corresponds to the
calibration you would get if the analyzer were fitted with a microphone with the nominal Open Circuit
Sensitivity do the following:
1) On the Setup display (Full tab):
–SetInput, Transd. Used to the microphone that you intend to substitute
–SetInput, Input to Top Socket
2) Calibrate the analyzer by typing in the nominal sensitivity as the Sensitivity on the Calibration
display. For Weatherproof Microphone Unit Type 4184-A, the nominal sensitivity is the microphone’s
Open Circuit Sensitivity (10.9 mV/Pa), attenuated by the Microphone Preamplifier ZE-0773’s
nominal attenuation (0.20 dB), which equals 10.66 mV/Pa. Do not press the Start Calibration
button.
3) Connect an electrical sinusoidal signal with a frequency of 251.2 Hz to the Electrical Substitute for
Microphones and adjust the amplitude of this signal until LZF (or LCF) displays 124.00 dB in the
Calibration display. This electrical amplitude is the 124.00 dB reference for the electrical tests. The
amplitude will typically be 359.9 mV. This is due to the attenuation of the Electrical Substitute for
Microphones (nominal 0.55 dB).
3.7.1 Signal Sources for Immunity Test
Acoustical Source for Testing According to IEC 61672, IEC 60651 and IEC 60804
The acoustic signal, which is used during the Immunity test according to IEC 61672, IEC 60651 and
IEC 60804, is applied to the microphone through a ½ plastic hose (a normal water hose) – from a source
outside the test area. In this way, the acoustic source is not affected by the RF or magnetic field. The
plastic hose is mounted on Adapter for Hose 210411, which is screwed on the microphone in place of the
windscreen. The source may be a normal entertainment earphone.
To prevent the acoustic source from being affected by acoustic noise in the surroundings, a method such as
the one listed in Hand-held Analyzer Types 2250, 2250-L and 2270 Instruction Manual BE 1712 can be
used.
Electrical Source for Testing According to IEC 61260
The short-circuit of the Input signal may be achieved by short-circuiting the electrical substitute for
microphones mounted on the microphone preamplifier.

7
Chapter 4
Specifications
4.1 Specifications
Specifications are given for the configurations detailed in Chapter 1.
Unless specifically noted, specifications are given as typical data under Reference Environmental
Conditions, and with the system calibrated to the nominal microphone open circuit sensitivity.
NOTE: The specifications given here for the Z-weighting, as defined in IEC 61672–1, are also valid for
the Lin response, as defined in IEC 60651.
4.4 Reference Conditions for Acoustic Calibration
Reference Level Range: In Single-range applications only one level range exists and this is the reference
level range. In Multi-range applications the reference level range is High Range.
Reference Sound Pressure Level: 124.00 dB re 20 Pa
Reference Frequency: 251.2 Hz
4.5 Microphone
Weatherproof Microphone Unit Type 4184-A which includes Microphone Preamplifier ZE-0773:
Type: Weatherproof Microphone Unit
Nominal Open Circuit Sensitivity: 10.9 mV/Pa, (corresponding to –39.25 dB re 1 V/Pa) ± 1.5 dB
Cartridge Capacitance: 18 pF (at 250 Hz)
Nominal Preamplifier Attenuation: 0.2 dB
Extension Cables between Microphone and the Analyzer: Up to 100 m without degradation of the
specifications. NOTE: EMC is only tested with a 10 m cable (AO-0697-D-100)
Microphone Reference Point: The point on the microphone's axis at the sound opening of the
microphone. The sound opening is 118 mm above the surface at the bottom of the windscreen mounting
thread.
Reference Direction: Two different reference directions of Sound Incidence:
•4184-A 0(Top): This reference direction is defined as the inward direction toward the Microphone
Reference Point on the microphones rotational axis, coming from the opposite direction of the
electrical output
•4184-A 90(Side): This reference direction is defined as the inward direction toward the Microphone
Reference Point perpendicular to the microphones rotational axis

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE17128
4.6.2 Typical Low-frequency Responses
The typical Low-frequency Responses for Z-frequency weighting are given in Fig.4.2. The Electrical
Responses are for the rear (Input) socket. The Acoustical Responses include Weatherproof Microphone
Unit Type 4184-A (which again includes Microphone Preamplifier ZE-0773).
Fig.4.2 Typical low-frequency responses
The Low-frequency Responses depends on the state of the Extended Low Frequency parameter on the
Setup display, under Input.
The Low-frequency Responses are not influenced by the microphone accessories described in
section .1.2.4.
The Low-frequency Responses for introduction of the electrical signal through the recommended means to
substitute the microphone with an electrical input facility (see section 3.5) differs from the electrical
responses because it also includes Microphone Preamplifier ZE-0773.
4.6.5 Free-field Frequency Responses
The free-field frequency responses for plane progressive sinusoidal sound waves incident from the
reference direction with Z-frequency weighting are provided in Fig.4.6a and Fig.4.6b, Table A.4a and
Table A.4b. The tables also provides the ‘Expanded Uncertainties of Measurement’ required by
IEC 61672–1, see the start of section 4.6 in the Instruction Manual.
Fig.4.3 Weatherproof Microphone Unit Type 4184-A is not specified without windscreen
Fig.4.4 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.5 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
-4
-2
0
2
4
dB
110100
Hz
Electrical Response, Extended Low Frequency 'On'
Electrical Response, Extended Low Frequency 'Off'
Acoustical Response with Type 4184-A, Extended Low Frequency 'On'
Acoustical Response with Type 4184-A, Extended Low Frequency 'Off'
110400

CHAPTER 4
Specifications 9
Fig.4.6a 4184-A 0°(Top), Free-field reference direction frequency response for Weatherproof Microphone Unit
Type 4184-A and the analyzer’s electrical response with the Microphone Preamplifier connected to a
microphone extension cable. Corresponds to the “Acoustical Response” column in Table A.4a
Fig.4.6b 4184-A 90°(Side), Free-field reference direction frequency response for Weatherproof Microphone Unit
Type 4184-A and the analyzer’s electrical response with the Microphone Preamplifier connected to a
microphone extension cable. Corresponds to the “Acoustical Response” column in Table A.4b
Fig.4.7 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.8 Weatherproof Microphone Unit Type 4184-A is not specified together with Outdoor Microphone Kit UA-1404
4.6.6 Diffuse-field Frequency Responses
The diffuse-field frequency responses (also called random-incidence frequency responses) with
Z-frequency weighting are provided in Fig.4.10 and Table A.8.
Fig.4.9 Weatherproof Microphone Unit Type 4184-A is not specified without windscreen
100 1000 10000 Hz
-4
-2
0
2
4
dB
110401
100 1000 10000 Hz
-4
-2
0
2
4
dB
110402

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE171210
Fig.4.10 Both reference directions, Diffuse-field frequency response for Weatherproof Microphone Unit Type 4184-A
and the analyzer’s electrical response with the Microphone Preamplifier connected to a microphone extension
cable. Corresponds to the “Acoustical Response” column in Table A.8
Fig.4.11 Weatherproof Microphone Unit Type 4184-A is not specified together with Outdoor Microphone Kit UA-1404
4.7 Directional Responses
This section gives directional responses for plane progressive sinusoidal sound waves normalised to the
response in the reference direction. The directional responses are given as tables in Appendix A.
The sensitivity variation graphs show the absolute maximum difference between the sensitivities at any
two sound incidence angles within the specified interval of angles. For example, at each frequency the
value for ±30° is the difference between the highest and the lowest sensitivity found in a circular cone with
an opening angle of 60°, the top at the Microphone Reference Point and with the reference direction of
incidence as the axis. Because the angle interval defines a three-dimensional geometric shape there is only
one set of graphs with sensitivity variations, also where the directional response is shown for two planes.
The graphs show the maximum variation for the two measurement planes combined. The sensitivity
variations are also given as tables in Appendix A.
Limit curves are drawn on the sensitivity variation graphs in the following sections. These curves
represent the IEC 61672–1 limits, reduced by the ‘Maximum Expanded Uncertainties of Measurement’
from Appendix A of IEC 61672–1. The ‘Maximum Expanded Uncertainties of Measurement’ used here
are the maximum uncertainties that a test organisation may have on its measurements when it performs
conformance tests according to IEC 61672.
Fig.4.12 Weatherproof Microphone Unit Type 4184-A is not specified without windscreen
Fig.4.13 Weatherproof Microphone Unit Type 4184-A is not specified without windscreen
Fig.4.14 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.15 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.16 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
100 1000 10000 Hz
-4
-2
0
2
4
dB
110409

CHAPTER 4
Specifications 11
Fig.4.17 Directional response for Weatherproof Microphone Unit Type 4184-A with the Microphone Preamplifier
connected to a microphone extension cable. Corresponds to Table A.31 to Table A.33. The sound incidence
angles are for 4184-A 0°(Top)’s reference direction. For 4184-A 90°(Side), subtract 90°from the angles in
the plots to get the sound incidence angle
0°
30°
60°
90°
120°
150°
180°
210°
240°
270°
300°
330°
-25
-20
-15
-10
-5
0
5
dB
d)
0°
30°
60°
90°
120°
150°
180°
210°
240°
270°
300°
330°
a: 630 Hz, b: 1600 Hz, c: 4000 Hz, d: 10000 Hz
a: 800 Hz, b: 2000 Hz, c: 5000 Hz, d: 12500 Hz
a: 1000 Hz, b: 2500 Hz, c: 6300 Hz, d: 16000 Hz
a: 1250 Hz, b: 3150 Hz, c: 8000 Hz, d: 20000 Hz
-25
-20
-15
-10
-5
0
5
dB
c)
0°
30°
60°
90°
120°
150°
180°
210°
240°
270°
300°
330°
-25
-20
-15
-10
-5
0
5
dB
b)
0°
30°
60°
90°
120°
150°
180°
210°
240°
270°
300°
330°
-25
-20
-15
-10
-5
0
5
dB
a)
0°
270° 90°
110110

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE171212
Fig.4.18a 4184-A 0°(Top), sensitivity variations for Weatherproof Microphone Unit Type 4184-A with the Microphone
Preamplifier connected to a microphone extension cable, at sound incidence angles within ±
 °from the
reference direction. Corresponds to Table A.34a
± 150°
0
5
10
15
20
dB
100 1000 10000 Hz
± 90°
0
5
10
15
20
dB
100 1000 10000 Hz
± 30°
0
5
10
15
20
dB
100 1000 10000 Hz
110111

CHAPTER 4
Specifications 13
Fig.4.18b 4184-A 90°(Side), sensitivity variations for Weatherproof Microphone Unit Type 4184-A with the Microphone
Preamplifier connected to a microphone extension cable, at sound incidence angles within ±
 °from the
reference direction. Corresponds to Table A.34b
Fig.4.19 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.20 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.21 Weatherproof Microphone Unit Type 4184-A cannot be mounted directly on the analyzer
Fig.4.22 Weatherproof Microphone Unit Type 4184-A is not specified together with Outdoor Microphone Kit UA-1404
Fig.4.23 Weatherproof Microphone Unit Type 4184-A is not specified together with Outdoor Microphone Kit UA-1404
4.8 Self-generated Noise
Self-generated noise is given for nominal microphone Open Circuit Sensitivity, Sound Field Correction
set to Free-field and no microphone accessories selected.
± 90°
0
5
10
15
20
dB
100 1000 10000 Hz
± 30°
0
5
10
15
20
dB
100 1000 10000 Hz
110112

Weatherproof Microphone Unit Type 4184-A – Supplement to Instruction Manual BE171214
4.8.1 Maximum Broadband Self-generated Noise
4.8.2 Typical Broadband Self-generated Noise
Table 4.1
Maximum broadband
self-generated noise Maximum
Noise
Frequency Weighting
A-weighting
(dB) B-weighting (dB) C-weighting (dB) Z-weighting*
(dB)
*. minimum 120 seconds LZeq
Z-weighting*
Extended Low
Frequency
(dB)
Single-range
Microphone 21.1 19.7 19.7 23.7 23.7
Electrical 29.0 27.6 28.1 33.3 44.3
Total 29.7 28.3 28.7 33.8 44.3
High Range
Microphone 21.1 19.7 19.7 23.7 23.7
Electrical 47.9 46.3 46.3 51.1 51.9
Total 47.9 46.3 46.3 51.1 51.9
Low Range
Microphone 21.1 19.7 19.7 23.7 23.7
Electrical 29.0 27.6 28.1 33.3 44.3
Total 29.7 28.3 28.7 33.8 44.3
Table 4.2
Typical broadband
self-generated noise Typical
Noise
Frequency Weighting
A-weighting
(dB) B-weighting (dB) C-weighting (dB) Z-weighting*
(dB)
*. minimum 120 seconds LZeq
Z-weighting*
Extended Low
Frequency
(dB)
Single-range
Microphone 20.1 18.7 18.7 22.7 22.7
Electrical 28.2 26.8 27.3 32.5 39.3
Total 28.8 27.4 27.9 32.9 39.4
High Range
Microphone 20.1 18.7 18.7 22.7 22.7
Electrical 44.4 42.8 42.8 47.6 48.1
Total 44.4 42.8 42.8 47.6 48.1
Low Range
Microphone 20.1 18.7 18.7 22.7 22.7
Electrical 28.2 26.8 27.3 32.5 39.3
Total 28.8 27.4 27.9 32.9 39.4