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Measurement Microphone Guide
Your guide to selecting the right measurement microphone
Measurement microphones are available in many types covering various frequency ranges, dynamic ranges and application situations. GRAS measurement microphones are amongst the world's best.
With this guide, you can find help to select the right measurement microphone for your applications. Get introduced to selecting externally polarized or prepolarized microphones, free-field, pressure or random incidence microphones as well as learning about the dynamic range of a microphone and the frequency range of a microphone.
Download the Microphone Guide >
Externally polarized microphone or prepolarized microphone
Can you tell the difference?
All GRAS measurement microphones are of the condenser type.
This requires a polarization voltage which can either be supplied from an external power supply or the microphone itself can be polarized by injecting a permanent electrical charge into a thin PTFE layer on the microphone backplate.
Free-field microphone or Pressure microphone or Random incidence microphone
Which one should you choose?
There are three types of measurement microphones: Free-field, Pressure, and Random incidence.
You can see the differences between these three types of measurement microphones at the higher frequencies, where the size of a microphone becomes comparable with the wavelengths of the sound being measured.
Dynamic range of a microphone
Which levels can the microphone handle?
The dynamic range of a microphone is defined as the range between the lowest level and the highest level which the microphone can handle.
This is not only a function of the microphone alone, but also of the preamplifier used with the microphone. The dynamic range of a microphone is, to a large extent, directly linked to its sensitivity.
Frequency range of a microphone
Which one should you choose?
The frequency range of a microphone is defined as the interval between its upper limiting frequency and its lower limiting frequency.
With today’s microphones you can cover a frequency range starting from around 1Hz and reaching up to 140 kHz.
