GRAS RA0045-S9 Externally Polarized Ear Simulator Based on IEC 60318-4 (60711), High Pressure

Standards: IEC 60318-4 (based on), ITU-T P.57
Eff vol: 1260 mm³ @ 500 Hz
Res freq: 13.5 kHz ±1 kHz

Technology

Introduction

The RA0045-S9 Ext Pol Ear Simulator is a special type of ear simulator for making high level acoustic measurements on earphones coupled to the human ear by ear inserts such as tubes, ear moulds, or ear tips. It has an input impedance closely resembling that of an average human ear, and, as a result, loads a sound source in very much the same way.

It is based on the following international requirements:

  • IEC 60318-4: Occluded-ear simulator for the measurement of earphones coupled to the ear by ear inserts.
  • ITU-T Recommendations P.57 (08/96) Series P: Telephone transmission quality, Objective measuringapparatus: Artificial ears.

It is measured and calibrated according to the ITU-T Recommendation P.57.

Design

The RA0045-S9 embodies a number of carefully designed volumes connected via well-defined and precisely tuned resistive grooves. In an equivalent electrical circuit, capacitors would represent the volumes, and inductance and resistance would represent respectively air mass and air flow within the resistive groves.

It includes a GRAS 40BH 1/4" Ext. Polarized Pressure Microphone, High Pressure and each RA0045-S9 is individually calibrated with this specific microphone.

Typical Applications and Use

The RA0045-S4 is for measurements on earphones and hearing aids coupled to the human ear by ear inserts such as tubes, ear moulds, or ear tips.

In accordance with ITU-T Recommendation P.57, it can be used with the following GRAS pinna simulators for testing telephones:

A comprehensive range of accessories for making measurements in accordance with IEC 60318-4 are available. See the tab Ordering info.

Compatibility

The RA0045-S9 can be used with a standard LEMO preamplifier, e.g. the GRAS 26AC 1/4" Preamplifier.

Specifications

Theoretical dynamic range lower limit with GRAS preamplifier
dB(A)
62
Theoretical dynamic range upper limit with GRAS preamplifier @ +120 V / ±60 V power supply
dB
193
Resonance frequency
kHz
13.5
Coupler volume
mm³
1260 @ 500 Hz
Temperature range, operation
°C / °F
Temperature coefficient @250 Hz
dB/°C / dB/°F
0.05
Humidity range non condensing
% RH
0 to 75
ANSI standard
S3.7
IEC standard
Based on 60318-4
ITU-T recommondations
P.57 Type 2
CE/RoHS compliant/WEEE registered
Yes/Yes, Yes
Weight
g / oz
52 / 1.8
Specification Conditions

Typical frequency response

GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.

Dimensions

Ordering info

 Optional items

GRAS RA0088

In Ear Adapter

GRAS GR0433

Calibration Adapter

GRAS GR0434

Stop Washer

GRAS GR0436

Tube Adapter

GRAS GR0437

Ear-mould Simulator

GRAS GR0438

Retention Ring

GRAS GR0440

Tube Adapter

GRAS RA0056

Low-leak Pinna Simulator

GRAS RA0057

High-leak Pinna Simulator

GRAS 26AC

26AC 1/4" Standard Preamplifier with 3 m Integrated Cable

GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.

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