Maximum sound pressure level of a microphone up to 170dB
Most microphones can easily measure sound levels over 100dB. At higher levels, many microphones are overloaded and, depending on the design, artifacts like distortion occur. These artifacts can massively change the sound impression and falsify measurement results.
We can reach high sound levels >100dB with our voice, easily. High SPL also occur close to speakers. High sound levels are relevant in occupational safety. Typical regolatory requirements are a measuring system with a linear range up to 140dB RMS. High sound levels naturally occur in the area of explosions or gunshots.
With well established manufacturers of acoustic measurement technology (B&K, GRAS, MTG, PCB, 01dB, NTI, etc.) you can rely on the manufacturer's information. You just have to make sure that the preamplifier and all signal stages can also handle this high voltage. We have written a basic article on this .
Even with high quality mics, it is advisable to check the performance with high sound levels in real world.
For cheaper microphones, the information about the maximum sound level is often questionable.
Do the values refer to the capsule or the entire chain?
If there are any uncertainties and you would like to measure high levels, you should have your system/microphone measured by us.
How do we measure the maximum sound level?
We use a high-performance pressure chamber that we measured with a reference microphone.
We can generate sound levels above 170dB.
The evaluation is carried out with our audio analyzer APX 555 from Audio Precsion
We measure the distortion (THD) depending on the level. A typical limit sound level is given at a harmonic distortion factor (THD) of 3%.
Typically we measure at 1600Hz. We achieve the highest sound level in our setup at 3000Hz.
At other frequencies, the maximum achievable sound level is slightly lower (approx. 3dB). However, we still achieve values that are above most measurement microphones.
We can measure microphones that are smaller than 3cm in diameter (they need to fit in the chamber)
Price on request
