The IEC 60318-4 ear simulator is widely applied in verfication of frequency response of acoustic products, e.g. in the consumer audio industry, but also for measurements on hearing aids. It is recognized for its ability to simulate the acoustic load as presented by the ear. Placing a headphone on a standardized ear simulator, e.g. a GRAS RA0045 Ear Simulator ensures that the headphone is facing the same acoustic input impedance as a real human ear would provide.

An ear simulator based on the standard IEC 60318-4 is therefore necessary to obtain a realistic acoustic transmission line from the output of the transducer (e.g headphone or a hearing aid) placed in a known measurement plane (eg. the ear entrance point) to the ear drum point in the ear simulator. However, the tradicional IEC 60318-4 (GRAS RA0045) ear simulator has an undamped length resonance at 13.5 kHz that makes it difficult to use for high-frequency testing.Therefore, GRAS has introduced two improved variants of the IEC 60318-4 ear simulator. They retain a firm footing in the standard but improve the ability to measure at high frequencies. Discover the evolution of the IEC 60318-4 ear simulators here.

The Standard IEC 60318-4 (711) Ear Simulator (GRAS RA0045)

It has a step half-wave resonance at 13.5 kHz which effectively limits its usefulness to below at least 10 kHz. It uses a ½" microphone.
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The High-Frequency Ear Simulator (GRAS RA0401/02)

It has a dampings system that attenuates the half-wave resonance at 13.5 kHz and thus extends the useful frequency range to 20 kHz. It uses a ½" microphone. Learn more

The Hi-Res Ear Simulator (GRAS RA0403/04)

It also has a damping system that attenuates the length-related resonances above 10 kHz, but the use of a ¼” microphone extends the useful frequency range to 50 kHz and beyond. Learn more

The Broadest Range of Ear Simulators

GRAS offers the industry’s broadest range of ear simulators and couplers: A full range of IEC 60318-1 to 5 ear simulators, complemented by a number of improved versions of the standardized IEC 60318-4 ear simulator. This range of ear simulators comprises:

> The standardized IEC 60318-4 ear simulator
> A low-noise version for measurements down to 10.5 dB
> A high-frequency version for measurements up to 20 kHz
> A Hi-Res version for measurements up to 50 kHz

Whether your need is IEC-standardized testing, improved standardized testing with anthropometric pinnae or testing up to 20 kHz or even 50 kHz, we have preconfigured ready-to-use solutions. 

LEARN ABOUT OUR TEST SOLUTIONS

If you need an even more highly specialized test set-up tailored to your specific needs, we can help you with a customized solution – contact your local GRAS partner for further information.