Frequently Asked Questions

Mouth Simulators

Can I mount 44AA or 44AB mouth simulators inside the KEMAR head?


What is the difference between a pistonphone and a sound calibrator?

My microphone has been calibrated some years ago. Can I still trust the calibration or should it be re-calibrated?

How can I get the calibration data from the TEDS chip? Is it possible to freely read and write the TEDS chip data?

Should I use a correction factor with my pistonphone or calibrator when calibrating my ear simulator?

Acoustical Test Fixtures

Can I configure KEMAR for measurements of active-noise-cancellation (ANC) and Bluetooth headphones/headsets electrical circuit hiss noise?

I have problems fitting in-ear headphones in the standardized pinna. How does it affect the accuracy of my measurements?


Why do I need a preamplifier?

What is the difference between Traditional (LEMO) and CCP preamplifiers?

Ear Simulators

Are the RA0401 and RA0402 High Frequency Ear Simulators fulfilling the IEC 60318-4 standard?

Are the new RA0403 and RA0404 Hi-Res ear simulators better than the RA0401 and RA0402 High-Frequency ear simulators?


I dropped my microphone on the floor. How does it affect the sensitivity and frequency response?

What are the different types of microphones available depending on the type of soundfield?

What are the free-field and random incidence corrections? How should I use them?

How is the length of a cable affecting my measurement?

What are the benefits and limitation of using Prepolarized microphones with CCP preamps vs. Externally polarized microphones with Traditional preamps?

Are Prepolarized microphones a bad choice for high temperature operation?

What is a random incidence corrector?

How is a measurement microphone affecting the sound field?

Is it possible to measure down to and below the human hearing threshold?

What is special about the rugged NVH microphones?

Are there any differences between externally polarized and prepolarized microphones capsules?

What is a microphone set?

Can dust/dirt affect my measurement microphones?

What is the maximum level I can measure with a typical ½” free-field microphone?