BRUEL & KJAER 4185 User Manual
  1. Manuals
  2. Brands
  3. BRUEL & KJAER Manuals
  4. Measuring Instruments
  5. 4185
  6. User manual
BRUEL & KJAER 4185 User Manual

BRUEL & KJAER 4185 User Manual

Ear simulator for telephonometry
Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
USER MANUAL
Ear Simulator for Telephonometry
Type 4185
BR 2309 – 11
English

Advertisement

Table of Contents
loading

Related Manuals for BRUEL & KJAER 4185

Summary of Contents for BRUEL & KJAER 4185

  • Page 1 USER MANUAL Ear Simulator for Telephonometry Type 4185 BR 2309 – 11 English...
  • Page 3 Ear Simulator for Telephonometry  Type 4185 User Manual www.bksv.com BR 230911 September 2015 ...
  • Page 4 Danger Signals an imminent hazardous Health and Safety Considerations situation, which, if not avoided, will This apparatus has been designed and tested result in death or serious injury in accordance with IEC/EN 61010–1 and Safety Requirements for ANSI/UL 61010–1 Warning Signals possibly hazardous Electrical Equipment for Measurement, situation, which, if not avoided, will Control and Laboratory Use...
  • Page 5 Mechanical Hazards Waste Handling Brüel & Kjær complies with the EU’s Waste Caution: Whenever it is likely that the correct Electrical Electronic Equipment function or operating safety of the (WEEE) Directive, which issues the apparatus has been impaired, it following waste handling instructions: must be made inoperative and be •...
  • Page 6 Brüel & Kjær has made every effort to ensure Brüel & Kjær and all other trademarks, service the accuracy of the information contained in marks, trade names, logos and product names this document. No responsibility is accepted are the property of Brüel & Kjær or a third- for any errors or omissions herein.

  • Page 7: Table Of Contents

    Contents CHAPTER 1 Description.................. 1 What’s in the Case ................ 2 Typical Configuration .............. 4 CHAPTER 2 Calibration.................. 5 Acoustic Impedance.............. 5 Frequency Sensitivity Response............ 6 Absolute Sensitivity............... 8 Calibrating Type 4185 .............. 9 CHAPTER 3 Handling the Ear Simulator...............  11 Assembling Type 4185 .............. 11 Adjusting the Ear Simulator Force .......... 12 Protecting the Ear Simulator............ 13 More Information ............... 13 CHAPTER 4 Acoustic Properties of the Coupler ...........  15 Equivalent Diagrams .............. 15 CHAPTER 5 Specifications ...................  19 CHAPTER 6 Glossary ...................  21...

  • Page 9: Description

    It enables electroacoustic measurements on telephone handsets to be carried out under well-defined acoustical conditions. Type 4185 fulfils the requirements of Rec. ITU-T P.57 Type 1 and IEC 60318–1 as well as all relevant ITU-T, IEEE and BS recommendations.

  • Page 10: What's In The Case

    What’s in the Case What’s in the Case In the carrying case, you receive all the necessary parts for Ear Simulator for Telephonometry Type 4185: Fig.1.2 Parts of Type 4185 • Low-noise Cable AO-0122-D-030, for the miniature sound source (A) • 4 × Soft Seal YJ-0431 (B) • Adaptor Sleeve for Acoustic Coupler DB-1164 (C) •...
  • Page 11 Chapter 1 – Description 1.1.1 The Acoustic Coupler Type 4185 consists of an acoustic coupler that has a built-in miniature sound source for seal checking, a microphone and a preamplifier. The seal between Type 4185 and the handset under test must be completely tight. The quality of this seal can be verified using the miniature sound source located inside the acoustic coupler.

  • Page 12: Typical Configuration

    Typical Configuration Typical Configuration Type 4185 can be used with a wide range of Brüel & Kjær telephone test systems. The typical configuration is with Telephone Test Head Type 4602-B. In this typical configuration, Type 4185 is mounted directly in the test head for tests on telephone handset receivers for measuresments on sealed, supra-aural and supra-concha earphones.

  • Page 13: Calibration

    ERP. By measuring the sound pressure at the ERP from the high acoustic impedance sound source, the acoustic input impedance of the ear simulator can be calculated. The impedance is displayed in decibels relative to 1 acoustic ohm (1 Pa·s/m ). See Fig. 2.1. Ear Simulator for Telephonometry Type 4185 User Manual...

  • Page 14: Frequency Sensitivity Response

    Frequency Sensitivity Response Fig.2.1 Typical acoustic impedance for Ear Simulator Type 4185 and the standardized ITU–T Rec. P.57 Type 1 curve with which Type 4185 complies Acoustic Impedance for Type 4185, re 1 Pa s/m ITU-T P.57 Typical 970388e Frequency Sensitivity Response The frequency sensitivity response is defined as the modulus of the ratio of output voltage of the ear simulator to input sound pressure at the ERP.
  • Page 15 1 dB up to 4 kHz (see Fig. 2.2). Hence, the frequency dependency is often ignored for Type 4185 – the ear simulator is considered as measuring at the ERP and the measurements can be used directly without need for further correction.

  • Page 16: Absolute Sensitivity

    Absolute Sensitivity Fig.2.2 Open‐ and closed‐ear frequency sensitivity responses for the ear simulator Frequency Sensitivity Response for Type 4185 , re 1 kHz Open-ear Frequency Sensitivity Response Closed-ear Frequency Sensitivity Response (Hz) 970377/1 Absolute Sensitivity The absolute sensitivity at 1 kHz in V/Pa is defined as the modulus of the ratio of the absolute output voltage of the ear simulator to the input sound pressure at the ERP.

  • Page 17: Calibrating Type 4185

    Sound Calibrator Type 4231. The absolute sensitivity at 1 kHz in [V/Pa] of Type 4185 as stated on the calibration chart is verified by applying the calibrator to the ½ microphone without the coupler. Pistonphone Type 4228 can also be used for calibration.
  • Page 18 By using the corrected calibration levels as given in Table 2.1, the open- or closed-ear sensitivity of the (assembled) ear simulator is obtained. Table 2.1 Corrected calibration levels for Sound Calibrator Type 4231  (open ear)  (closed ear) 4231,corrected 4231,corrected Type 4185 93.8 dB 93.3 dB  Calibrating the ½  Microphone with Sound Calibrator  Type 4231 To calibrate the microphone, ensure that the standard green adaptor (UC-0210) is inserted in the middle of the calibrator.

  • Page 19: Handling The Ear Simulator

    Chapter 3 Handling the Ear Simulator Assembling Type 4185 Ring for Acoustic Coupler DB-1160, Black Collar YJ-0430 and 1 × Soft Seal YJ-0431 are all supplied already attached to Acoustic Coupler UA-1110. If UA-1110 and DB-1160 are separate, simply screw them together. Fit the microphone and preamplifier as follows: 1) Insert Preamplifier Type 2669 into Adaptor Sleeve DB-1164 at the adaptor sleeve’s small end.

  • Page 20: Adjusting The Ear Simulator Force

    (see Fig. 3.2). 4) Use the built-in seal check facility of Type 4185. The procedure is very similar to using a low test frequency as explained above, but...

  • Page 21: Protecting The Ear Simulator

    More Information For more helpful hints in using Brüel & Kjær ear simulators for telephone testing, see the application note, “Improving Telephone Handset Performance” (BO 0455) included with your instrument. Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 22 More Information Ear Simulator for Telephonometry Type 4185 User Manual...

  • Page 23: Acoustic Properties Of The Coupler

    Fig. 4.1 shows the physical construction of Acoustic Coupler UA-1110 and the associated electrical component names. Fig.4.1 Cross‐section  of  Acoustic  Coupler  UA‐1110.  The  electrical  component  names refer to the electrical equivalent diagram below 970415e Fig. 4.2 shows the equivalent diagram and associated component values for the ear simulator. Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 24 Equivalent Diagrams Fig.4.2 Electrical equivalent diagram of Ear Simulator Type 4185 using an impedance analogy.  The  circuit  is  seen  from  the  acoustical  side  with  associated component values in acoustic units Pa · s 5 × 10 Pa · s 6.5 × 10 Pa · s 20 × 10 Input (acoustic impedance) 10 × 10 –12 17.6 ×...
  • Page 25 Chapter 4 – Acoustic Properties of the Coupler Fig.4.3 Simulated acoustic impedance for Type 4185 compared to a typical measured impedance curve Acoustic Impedance for Type 4185, re 1 Pa s/m Typical Simulated 970375e Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 26 Equivalent Diagrams Ear Simulator for Telephonometry Type 4185 User Manual...

  • Page 27: Specifications

    Chapter 5 Specifications Specifications – Ear Simulator for Telephonometry Type 4185 General Miniature Sound Source STANDARDS TYPICAL SENSITIVITY Acoustic performance according to: –7 dB re 1 Pa/V (at 250 Hz, with flat surface  • ITU‐T Rec. P.57 Type 1 termination) • IEC 60318–1 MINIMUM SENSITIVITY FREQUENCY RANGE –11 dB re 1 Pa/V (at 250 Hz) 100 Hz to 4 kHz MAXIMUM INPUT VOLTAGE PREAMPLIFIER AND MICROPHONE 10 V Preamplifier: Type 2669 (included)
  • Page 28 Note: The above is only guaranteed using accessories listed in this  manual. Temperature IEC 60068–2–1 & IEC 60068–2–2: Environmental Testing. Cold and Dry  Heat. Operating Temperature: 5 to 40 C (41 to 104 F) Storage Temperature: –25 to +70 C (–13 to +158 F) IEC 60068–2–78: Damp Heat: 90% RH (non‐condensing at 40 C  Humidity (104 F)). Mechanical Non‐operating: IEC 60068–2–6: Vibration: 0.3 mm, 20 m/s , 10 – 500 Hz IEC 60068–2–27: Shock: 1000 m/s   IEC 60068–2–29: Bump: 1000 bumps at 250 m/s   Ear Simulator for Telephonometry Type 4185 User Manual...

  • Page 29: Glossary

    ITU that publishes recommendations regarding all aspects of telecommunication Abbreviation for decibel, used to express a logarithmic power ratio between two quantities. (in dB) = 10 log ) where is the reference value Abbreviation for Deutsches Institut für Normung Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 30 ITU-T Rec. P.58 International Electrotechnical Commission Institute of Electrical and Electronics Engineers IEEE Loudness Rating. A single number, expressed in dB, determined either subjectively or objectively, representing the loss in a telephone system Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 31 It is also used to refer to an adaptor for the calibration of the mouth simulator and a corresponding filter used in OREM In a telephone system, the transmission path from a Sidetone speaker's mouth to his/her own ear Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 32 Sidetone Masking Rating. A single figure measure of STMR telephone sidetone path loss calculated as a loudness rating from a sidetone measurement See send Transmit Ear Simulator for Telephonometry Type 4185 User Manual...
  • Page 34 www.bksv.com © Brüel & Kjær. All rights reserved. ...

Table of Contents