HTC has put up a post on its blog talking about how the HTC One has distortion free recording by using dual membrane microphones. This means that if you're in the back of a classroom trying to record a lecture on your HTC One, during playback you won't have to deal with weird noises and an “unintelligible voice”.
Today's smartphones are created with a single-membrane microphone that is able to focus on high-sensitivity and better capabilities of capturing high audio levels. HTC is incorporating a technology called HTC BoomSound in the HTC One, which brings two dual-membrane microphones to the device to help record better audio.
How does this allow the HTC One to offer distortion free recording? Instead of the entire load put on a single-membrane microphone one membrane microphone will service a certain purpose. One will focus on high-sensitivity while the other is focused on high-sound pressure.
With this design, background noise has been significantly reduced thus making the quality of the recording substantially better than a single-membrane microphone. In other words, with the HTC One you can record a lecture in class with a very high sound quality. As they always say, “two is better than one”.