On the face of it, producing a set of noise cancelling headphones needs to be a comparatively easy challenge. However as [Pete Lewis] came upon, issues are usually not at all times as they appear. The result’s a deep dive into microphone specs, by which most of us may most likely be taught one thing.
Noise cancelling headphones have a set of microphones which offer anti-phase noise by an amplifier to the ‘telephones, thus in idea cancelling out the exterior noise. Since [Pete] is a musician this pair must be able to working at excessive noise ranges, so he checked the spec for his microphone and with an acoustic overload level at 124 dB for a 115 setting he was able to go.
Sadly these ‘telephones confirmed distortion, which brings us again to the acoustic overload level. That is the sound degree at which the microphone has 10% distortion, which is a really excessive determine, and definitely meant there was sufficient distortion to be audible on the decrease degree. After a seek for a better spec microphone and a transfer to a digital codec-based resolution with an ESP32 he finally cracks it although, resulting in a cheap set of noise cancelling headphones for high-noise environments.
If distortion pursuits you, it’s a topic we’ve visited previously.
Header picture: fir0002, GFDL 1.2.
