GRAS 45BB-16 KEMAR with Hi-Res Simulators for Test of Ear- and Headphones, 2-Ch CCP
Connection: Constant Current Power (0 V/CCP)
Channel(s): 2
ANSI: S3.36, S3.25
IEC: 60318-7
ITU-T Rec. P.57 Type 3.3
based on ITU-T Rec. P.58
The 45BB-16 KEMAR with TEDS is a manikin configured with pre-polarized hi-res ear simulators and anthropometric pinnae for dual-channel ear- and headphone test up to 50 kHz. Its corresponding LEMO equivalent is the GRAS 45BB-15 KEMAR.
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 60318-7:2017.
The GRAS 45BB KEMAR 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 the proximity and in the far-field.
As all the preconfigured 45BB KEMARs consist of the same basic 45BB 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 45BB 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 45BB-16 is a KEMAR head and torso for 2-channel ear and headphone test, with prepolarized hi-res ear simulators and anthropometric pinnae.
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 45BB-16 are the GRAS RA0404 Prepolarized Hi-Res Audio Ear Simulator and the KB5000/KB50001 Anthropometric Pinnae.
The Hi-Res Ear Simulator
The acoustic input impedance of the RA0404 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 RA0404 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 50 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, from 20 kHz to 50 kHz it is within ±3.2 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 40BD 1/4" prepolarized pressure microphone.
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 compared to the cylindrically or conically shaped ear canal extensions that are used with the standard pinnae.
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 possible to mount and dismount DUTs repeatedly without compromising the seal.
Read more about the Anthropometric Pinnae here.
Typical Applications
The anatomical shape of the pinna makes it possible to achieve a very good 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 mean that the low-frequency response is improved. It will allow you to reproduce base notes, as well as effectively measure (active & passive) attenuation.
With the hi-res audio ear simulator, it is now possible to make reproducible measurements up to 50 kHz. The 45BB-16 KEMAR is ideal for accurate and repeatable testing of hearing aids, headphones, earphones, and in-ear hearing protectors. Read more about the advantages of the high-resolution ear simulator here.
Performance and warranty
KEMAR is made of components from our standard portfolio and is manufactured of high-quality material and branded parts 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
Ordering info
Included items
GRAS 45BB | KEMAR Head & Torso, Non-configured |
Large Right Anthropometric Pinna 35 Shore OO | |
Large Left Anthropometric Pinnar 35 Shore OO | |
Prepolarized Hi-Res Audio Ear Simulator ( 2 pcs) | |
GRAS GR1874 | Ear Simulator Holder |
GRAS GR0408 | External Ear Canal |
GRAS GR0409 | Union Nut |
1/4" CCP Short Preamplifier (2 pcs) | |
Microdot-BNC Cable, 35 cm (2 pcs) | |
BNC-BNC Cable, 3 m (2 pcs) |
Optional items
Power Modules for Pre-polarized Ear Simulators and Microphones
GRAS 12AL | 1-Channel CCP Power Module with A-weighting filter |
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) |
Pistonphone (250 Hz, 114 dB +/- 0.08 dB) |
Pinna Simulators
GRAS KB5000 | Large Right Anthropometric Pinna 35 Shore OO |
Large Left Anthropometric Pinnar 35 Shore OO | |
KEMAR Small Right Straight Pinna 55 Shore OO | |
KEMAR Small Straight Pinna 55 Shore OO | |
KEMAR Large Straight Pinna 55 Shore OO | |
KEMAR Large Left Straight Pinna 55 Shore OO | |
KEMAR Small Right Straight Pinna 35 Shore OO | |
KEMAR Small Left Straight Pinna 35 Shore OO | |
KEMAR Large Right Straight Pinna 35 Shore OO | |
KEMAR Large Left Straight Pinna 35 Shore OO | |
KEMAR Large Right Tapered Pinna (VA-Style/SQ) 55 Shore OO | |
KEMAR Large Left Tapered Pinna (VA-Style/SQ) 55 Shore OO | |
KEMAR Large Right Tapered Pinna (VA-Style) 35 Shore OO | |
KEMAR Large Left Tapered Pinna (VA-Style) 35 Shore OO |
Ear Mould Simulators
GRAS KB0110 | Ear Mould Simulator for 2 mm Inner diameter tubing |
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 |
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 |
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. |
Extension Cables
GRAS AA0034 | BNC-BNC Cable, 2 m |
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 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 | Stand for KEMAR, Ø 35 mm |
Miscellaneous (incl. in 45BB)
GRAS KB0000 | KEMAR Handbook |
GRAS KB0010 | T-Shirt for KEMAR |
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.