What is far-field voice?
Far-field voice recognition is designed to recognize human speech in a noisy environment by using an array of microphones. Noise cancelling and beamforming technology is used to divide the target speech from noise. Artificial intelligence is at the heart of the voice recognition firmware.
Right away you should recognize this as a tool for capturing EVP’s.
The microphone array is a series of microphones placed on a circuit board. The microhpnes are connected to a processor that does all the computing. AI-powered smart speakers are popular devices that use far-field voice recognition. In a noisy room they can immediately pick-up human speech and listen for the key word that activates them. So, yes they are always listening – if you were wondering.
Can you hear me now?
These devices use multiple microphones to reduce the impact of noise. The iPhone increases the number of microphones with each generation. Smart speakers use up to seven microphones. They are usually laid out in a hexagonal formation. The delay between the microphones enables the device to identify the source of the voice and cancel out noise coming from other directions. This is called beamforming.
How does far-field pickup work? Sound is sent to a sensor which converts analog sound into digital 1’s and 0’s. Then it is processed by a processing microchip, where speech enhancement is applied using AI embedded algorithms. The final result is an enhanced signal that then feeds into a conventional model for speech recognition.
EVP’s and your recorder
Far-field voice is the next chapter in paranormal research. The opportunity to clean up noise and focus on human speech is tremendous. I investigated the possibility of creating a microphone array that could be used with a recorder to capture EVP’s. I found some interesting research articles and then the holy grail. A plug & play far-field microphone array already exists and at a decent price point. For under $70 you can have the power of a far-field voice microphone to plug into your recorder of choice. Many retailers have this, including AliExpress but I found the best price at SeeedStudio.com called the ReSpeaker USB Mic Array. It will need to be powered up using the USB port but comes with a line level audio jack that can be plugged into a recorder.