Related Manuals for G.R.A.S. 43AE
Summary of Contents for G.R.A.S. 43AE
- Page 1 Instruction Manual 43AE Ear Simulator Kit According to ITU-T Rec. P57 Type 3.2 43AE-S1 Ear Simulator Kit According to ITU-T Rec. P57 Type 3.2, prepolarized www.gras.dk LI0070 – 28 June 2017...
- Page 2 Revision History Revision Date Description 28 June 2017 Extracted from Earbook as separate document Any feedback or questions about this document are welcome at gras@gras.dk. Copyright Notice © 2005-17 G.R.A.S. Sound & Vibration A/S http://www.gras.dk Any technical documentation that is made available by G.R.A.S. is the copyrighted work of G.R.A.S.
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Page 3: Table Of Contents
2: Calibration ..................... 7 3: Placing the Ear Simulator on the Earpiece/Earphone ........8 4: Applying the Test Signal ................. 8 Frequency Response of the 43AE .............. 10 Warranty, Service and Repair ............11 Calibration ....................11 Warranty ....................11 Service and Repairs .................. -
Page 4: Introduction
Introduction The 43AE Ear Simulator Kit is for acoustically testing supra-aural earphones, telephone hand- sets and loudspeakers, and complies with the following international requirements: ITU-T Recommendation P .57 (08/96) “Serie P: Telephone Transmission quality. Objective measuring apparatus: Artificial ears”. - Page 5 Caution! When attach- ing RA0001 to the ¼ RA0045, use only 26AC " Preamplifier gentle finger force (shown) or 26CB Fig. 2. Exploded view of all the user-serviceable components of the 43AE Ear Simulator Kit LI0070 – 28 June 2017...
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Page 6: Additional Equipment
A/D and D/A conversions in order to simulate both a signal generator and an analyser. Fig. 3 shows a block diagram of a possible set-up for making tests. Signal from generator to earphone Computer with hardware 43AE with telephone and software for simulat- ing: a signal generator capable... -
Page 7: The 4 Stages Of The Test Procedure
Setting up the Ear Simulator, e.g. as shown in Fig. 3 Calibration check using the G.R.A.S. 42AA Pistonphone with a special adapter for the 43AE Placing the Ear Simulator over the earpiece of the telephone (see example in Fig. 4) Applying a signal to the telephone and analysing the output from the microphone. -
Page 8: 2: Calibration
The following procedure, using a G.R.A.S. Pistonphone, should preferably be carried out at the following times: before a first-time use of the 43AE to establish a baseline for subsequent checks thereafter at appropriate intervals to check for repeatability The Pistonphone must be fitted with a 1” Microphone Coupler RA0023 and used with a special Adapter RA0119 for the 43AE, both available from G.R.A.S. -
Page 9: 3: Placing The Ear Simulator On The Earpiece/Earphone
3: Placing the Ear Simulator on the Earpiece/Earphone In cases of production testing, this is normally taken care of automatically. Whether automatic or manual, the Ear Simulator must be centrally placed over the earpiece/earphone being tested so that the sound is transmitted directly into the Ear Simulator. See example in Fig. 4. 4: Applying the Test Signal The following describes typical procedures for applying: a swept signal... -
Page 10: Frequency Response Of The 43Ae
Fig. 6. Frequency response curves of the 43AE fitted with a low-leak pinna simulator re. 1 kHz. Frequency Response of the 43AE For measurement purposes, the 43AE is a simulation of an ear drum, ear canal and pinna The diaphragm of the built-in microphone simulates the ear drum and occupies the position known as the DRP . - Page 11 ERP at origin of X-Y-Z axes X-axis Z-axis Y-axis Fig. 7. Showing the basic configuration for testing the microphone of a telephone handset. The ear piece lies in the plane of the Y-Z axes. See Fig. 8 for geometrical details X-axis Approximate orientation of Lip...
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Page 12: Warranty, Service And Repair
Warranty, Service and Repair Calibration Before leaving the factory, all G.R.A.S. products are calibrated in a controlled laboratory environ- ment using traceable calibration equipment. We recommend a yearly recalibration at minimum, depending on the use, measurement environ- ment, and internal quality control programs. We recommend calibration prior to each use to ensure the accuracy of your measurements. -
Page 13: Appendix
Appendix The RA0045/RA0045-S1 Ear Simulator Introduction The RA0045/RA0045-S1 Ear Simulator is for making acoustic measurements on earphones coupled to the human ear by ear inserts such as tubes, ear moulds or ear tips. It is delivered with a built-in 40AG ½” pressure microphone and an individual calibration chart for the coupler-microphone combi- nation. - Page 14 Preamplifiers With the 43AE, the externally polarized RA0045 is delivered with a standard preamplifier, e.g. a 26AC ¼” Preamplifier fitted with an adapter. With the 43AE-S1 the prepolarized RA0045-S1 is delivered with the 26CB ¼” Preamplifier fitted with an adapter.
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Page 15: Level Calibration
Level Calibration This paragraph describes level calibration using a pistonphone. This is the kind of calibration you would most often perform prior to measuring. How to perform a frequency calibration is described on page 16. Do not attempt to remove the microphone from the RA0045. You will be calibrating the RA0045 as a whole with a Pistonphone fitted with a ½”... -
Page 16: Frequency Calibration Of The Ra0045
Frequency Calibration of the RA0045/RA0045-S1 This section describes how to perform a frequency calibration using a 40BP ¼” Microphone as sound source. Fig. 12 shows how to configure the coupler for calibration using the accessories provided, and Fig. 13 shows how these should be used with: 40BP ¼”... - Page 17 To analyser from Preamplifier RA0045 Ear Simulator set Computer with hardware up for calibration (see Figs. and software for simu- 6 and 7) lating a signal generator capable of generating logarithmically swept 14AA Actuator Supply tones and signal analysis From signal generator To RA0045 Fig.