GRAS 45BC-14 KEMAR with Mouth Simulator for High-Frequency Headset Test, 2-Ch CCP

Connection: CCP
Channel(s): 2
Standards: ANSI: S3.36, S3.25
IEC: 60318-4, based on 60318-7
Based on ITU-T Rec. P.57 Type 3.3 and
ITU-T Rec. P.58
Special feature: Built-in power amplifier for mouth simulator

The 45BC-14 KEMAR with TEDS is configured with anthropometric pinnae and prepolarized high-frequency ear simulators. Due to its design, realistic measurement in a sound environment as experienced by a human being using a headset is possible. In addition, the 45BC-14 is provided with a mouth simulator for testing the microphone in the headset. Its LEMO equivalent is GRAS 45BC-13.

Technology

Introduction

The KEMAR head and torso simulator was introduced by Knowles in 1972 and quickly became the industry standard for hearing-aid manufacturers and research audiologists (visit KEMAR.us to read the full story). It is based on worldwide average human male and female head and torso dimensions. It meets the requirements of ANSI S3.36/ASA58-2012 and IEC 60318-7:2011.

The current KEMAR Head and Torso has the same dimensions and acoustical properties as the original KEMAR, but has been developed further by GRAS to meet the industry’s demand for realistic measurements of hearing aids, headphones, and headsets. It provides acoustic diffraction similar to that encountered around the median human head and torso, both in proximity and in the far-field.

As all the preconfigured 45BC KEMARs consist of the same basic 45BC KEMAR Non-configured, plus a set of application-specific accessories, the full information about a given KEMAR configuration is obtained by combining the information about the 45BC KEMAR Non-configured and the information for a given configured version as found in the present text. Read about the non-configured KEMAR here.

TEDS Compatibility

All CCP-based KEMAR configurations are IEEE 1451.4 TEDS v. 1.0 compliant. If your measurement platform supports Transducer Electronic Data Sheets (TEDS), you will be able to read and write data like properties and calibration data.

Design

The 45BC-14 is a KEMAR with prepolarized high-frequency ear simulators and anthropometric pinnae for 2-channel ear and headphone test.

It is delivered fully configured, individually calibrated and ready for use. In addition to a system calibration certificate, a USB flash memory with simulation data is included.

The main configuration-specific components of the 45BC-14 are the GRAS RA0402 High-Frequency Ear Simulator and the KB5000/KB50001 Anthropometric Pinnae.

The 44AA Mouth Simulator according to ITU-T Rec. P51 with built-in power amplifier
The maximum continuous signal the mouth can produce in 1/3-octave bands is 100dB re. 20µPa in the frequency range of 100Hz to 16kHz. Its loudspeaker accepts an external signal either directly or via its built-in power amplifier (when power is applied).

The High-Frequency Ear Simulator
The acoustic input impedance of the RA0402 High-Frequency Ear Simulator closely resembles that of the human ear and, as a result, loads a sound source in very much the same way.  It 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.

The RA0402 High-Frequency Ear Simulator mitigates the limited usefulness of the standard IEC60318-4 ear simulator above 10 kHz. The steep resonance at 13.5 kHz has been replaced by a much-damped resonance and the useful frequency range is now extended to 20 kHz within a narrow tolerance band. It complies with IEC60318-4 and its acoustic transfer impedance is within the tolerance band specified by IEC60318-4. From 10 to 20 kHz the transfer impedance is within ± 2.2 dB, resulting in much-improved repeatability. Also, realistic THD measurements are now possible.

It is measured and calibrated according to IEC60318-4 and ITU-T Recommendation P.57 and delivered with a calibration chart specifying its sensitivity and frequency response.

It is delivered with a built-in GRAS 40AO 1/2" prepolarized pressure microphone.

Read more about RA0402 here.

The Anthropometric Pinna
Compared to the standardized pinna, the anthropometric pinna embodies several improvements to the concha and ear canal, combined with increased collapsibility of the helix, and improved mounting. It is made of soft silicone, 35 Shore OO hardness.

The external shape of the pinna is identical to that of the standardized KEMAR pinna, but concha and ear canal have been modified so that they closely mimic the properties of a real human ear. The ear canal has been extended and is now an integral part of the pinna, which seals directly against the ear simulator. Like the human ear, the ear canal has the 1st and 2nd bend, and the interface with the concha is oval. Fit and insertion consistency are much improved over the cylindrically or conically shaped ear canal extensions that are used with the standardized pinna.

The flexibility of the outer ear has been improved, and when mounting supra-aural and circum-aural headphones the pinna now collapses against the head very much like a human ear.

In addition to the traditional push mounting from the outside, the pinna is secured with two screws from the inside of KEMAR's head. These two screws ensure that the pinna is held firmly in place. Therefore, it seals perfectly against the ear simulator and the head, and it is now possible to mount and dismount DUTs repeatedly without compromising the seal.

Read more about the Anthropometric Pinnae.

Typical Applications

The anatomical shape of the pinna makes it possible to achieve an excellent fit and sealing with anatomically shaped in-ear transducers.

Controlling the insertion depth is easy, leading to good insertion consistency and highly improved repeatability and accuracy of measurements.

The improved fit and seal also means that the low-frequency response is improved. It will allow you to reproduce bass notes, as well as effectively measure (active & passive) attenuation.

With the high-frequency ear simulator, it is now possible to make realistic measurements up to 20 kHz. Read more about the advantages of the high-frequency ear simulator here.

Therefore, the 45BC-14 KEMAR is ideal for accurate and repeatable testing of headphones, earphones, and in-ear hearing protectors. In addition to this, the built-in mouth simulator makes it ideal for accurate and repeatable testing of headsets.

Performance and warranty

KEMAR is made of components from our standard portfolio, all manufactured of high-quality material and branded parts that were chosen and processed to ensure life-long stability and robustness. This enables us to offer a two-year warranty against defective materials and workmanship.
Exceptions: Microphones included in KEMAR as for these our normal five-year warranty applies. The warranty period for cables is six months.

Specifications

Set sensitivity @ 250 Hz (±2 dB)
mV/Pa
12.5
Set sensitivity @ 250 Hz (±2 dB)
dB re 1V/Pa
-38.5
Theoretical dynamic range lower limit with GRAS preamplifier
dB(A)
25
Theoretical dynamic range upper limit with GRAS CCP preamplifier
dB
150
Resonance frequency
kHz
13.5
Temperature range, operation
°C / °F
-30 to 60 / -22 to 140
Temperature range, storage
°C / °F
-40 to 65 / -40 to 149
Humidity range non condensing
% RH
0 to 95%
ANSI standard
S3.36, S3.25
IEC standard
60318-7
ITU-T recommondations
P. 58
Weight
g / oz
11.45 k / 404
MOUTH SIMULATOR
.
Output impedance
Ω
8
Maximum power, continuous
W
10
Maximum power, pulsed 2 sec.
W
50
Input impedance
20
Gain
dB
10
Input signal, max.
Vrms
2
Power supply, external
Vdc
24

Ordering info

Included items

GRAS 45BC

KEMAR Head & Torso with GRAS 44AA Mouth Simulator, non-configured

GRAS KB5000

KEMAR Large Right Anthropometric Pinna 35 Shore OO

GRAS KB5001

KEMAR Large Left Anthropometric Pinna 35 Shore OO

GRAS GR0408

External Ear Canal (for calibration, 2 pcs)

GRAS GR0409

Union Nut (for GR0408, 2 pcs)

GRAS GR1874

Ear Simulator Holder (2 pcs)

GRAS RA0402

High Resolution Ear Simulator, (Prepol.version, 2 pcs)

GRAS 26CS

1/4" CCP Standard Preamplifier with Microdot Connector, Very Short (2 pcs)

GRAS RA0001

Right Angled Adapter for 1/2" Microphone and 1/4" Preamplifier (2 pcs)

GRAS AA0018-S

Microdot-BNC Cable, 35 cm (2 pcs)

GRAS AA0035

3 m BNC - BNC Cable (2 pcs)

GRAS 46BD

1/4" CCP Pressure Standard Microphone Set

GRAS AA0070

Microdot-BNC Cable, 3 m

 

Optional items

Power Modules for Pre-polarized Ear Simulators and Microphones

GRAS 12AL

1-Channel CCP Power Module with A-weighting filter 

GRAS 12AQ

2-Channel Universal Power Module with signal conditioning and PC interface

 

For Ear Simulator Calibration

GRAS 42AP

Intelligent Pistonphone (250 Hz or 251.2 Hz, 114 dB +/- 0.05 dB)

GRAS 42AA

Pistonphone (250 Hz, 114 dB +/- 0.08 dB)

 

Pinna Simulators

GRAS KB5000

Large Right Anthropometric Pinna 35 Shore OO

GRAS KB5001

Large Left Anthropometric Pinnar 35 Shore OO

GRAS KB0060

KEMAR Small Right Ear 55 Shore OO

GRAS KB0061

KEMAR Small Left Ear 55 Shore OO

GRAS KB0065

KEMAR Large Right Ear 55 Shore OO 

GRAS KB0066

KEMAR Large Left Ear 55 Shore OO

GRAS KB1060

KEMAR Small Right Ear, 35 Shore OO 

GRAS KB1061

KEMAR Small Left Ear 35 Shore OO

GRAS KB1065

KEMAR Large Right Ear 35 Shore OO 

GRAS KB1066

KEMAR Large Left Ear 35 Shore OO

GRAS KB0090

KEMAR Large Right Ear (VA-Style/SQ) 55 Shore OO 

GRAS KB0091

KEMAR Large Left Ear (VA-Style/SQ) 55 Shore OO

GRAS KB1090

KEMAR Large Right Ear (VA-Style) 35 Shore OO 

GRAS KB1091

KEMAR Large Left Ear (VA-Style) 35 Shore OO 

 

Ear Mould Simulators

GRAS KB0110

Ear Mould Simulator for 2 mm inner diameter tubing 

GRAS KB0111

Ear Mould Simulator for 3 mm inner diameter tubing

 

Ear Canal Extension and Microphone Holder Kits (kits with 2 pcs and O-rings)

GRAS RA0237

Straight Ear Canal Extension Kit for KEMAR 

GRAS RA0238

VA-tapered Ear Canal Extension Kit for KEMAR 

GRAS RA0239

Ear Canal Extension Kit w. silicone lining for KEMAR

GRAS RA0240

Holder for long 1/2" microphone Kit for KEMAR 

GRAS RA0241

Holder for short 1/2" microphone Kit for KEMAR

GRAS RA0243

Holder for 1/4" microphone Kit for KEMAR

GRAS RA0244

O-ring kit for KEMAR, 2 pcs. 

GRAS RA0249

Straight Ear Canal Extension Kit for KEMAR,made of POM, for binaural hearing aid test

GRAS RA0250

Tapered Ear Canal Extension Kit for KEMAR,made of POM, for binaural hearing aid test

 

KEMAR Retrofit Kit for Binaural Hearing Aid Test

GRAS RA0251

KEMAR Retrofit Kit for Binaural Hearing Aid Test.

The Kit includes Ear Holder Plates, mounting bolts and the RA0249 and RA0250 Ear Canal Extension Kits.
Included items are made of POM, Nylon and Teflon.

 

Extension Cables

GRAS AA0034

BNC-BNC Cable, 2 m

GRAS AA0035

BNC-BNC Cable, 3 m 

GRAS AA0036

BNC-BNC Cable, 5 m

GRAS AA0037

BNC-BNC Cable, 10 m 

 

Flight Case

GRAS KM0094

 PELI Case for KEMAR

 

Simulation Model of 45BB KEMAR

GRAS KB3000 3D Simulation Model of KEMAR with large pinnae, stp file
GRAS KB3001 3D Simulation Model of KEMAR with small pinnae, stp file
GRAS KB3002 3D Simulation Model of KEMAR with anthropometric pinnae, stp file

 

Stand for KEMAR

GRAS AL0026

 Loudspeaker stand for KEMAR, Ø 35 mm

 

Miscellaneous

GRAS KB0000

KEMAR Handbook 

GRAS KB0010

T-Shirt for KEMAR 

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