Noise sensor technology, with two microphones on each earcup, picks up ambient noise and transmits the data to the HD Noise-Canceling QN1 processor. Using a new algorithm, the QN1's HD ANC processor then applies real-time ANC processing to a range of acoustic environments. Working together with a new Bluetooth® Audio SoC, it detects and adjusts to music and noise signals over 700 times per second.

Speak to Chat automatically stops the music and enters Transparent hearing mode when it detects your voice. It is useful when your hands are busy. The feature uses five built-in microphones and advanced audio signal processing technology. When the conversation ends, the music, or any other content you were listening to, resumes automatically.

The proximity sensor and two acceleration sensors in the headphones can detect whether you're wearing them or not and stop music accordingly, saving battery life. Not that it really needs to, because the WH-1000XM4 enjoys, like its predecessor, 30 hours of battery life. And if you still run out of battery and need to recharge in a hurry, you can get 5 hours of battery life in just 10 minutes with the optional AC adapter.

Thanks to Precise Voice Pickup technology, which combines five built-in microphones with advanced audio signal processing, the WH-1000XM4 delivers clearer voice quality to the other person on the phone.