Although smartphone users are happily recording their special moments in pristine 4K-resolution video, even expensive devices tend to fall apart when it comes to audio recording quality. Noise filtering and weak microphones usually bring out the worst of any recorded sound, and we can't recall being impressed with a smartphone's call quality over 3G/4G networks in a long time. Still, this is being worked on behind closed doors. According to an article by EETimes, high quality voice and audio are the next frontier for smartphones.
At MWC 2016, the media spoke to Andreas Urschitz, an executive at Germany's Infineon Technologies, and Matt Crowley – CEO of Vesper. The company provides its MEMS (Micro-Electro-Mechanical Systems) silicon to Hong Kong-based AAC Technologies, and partnering startup Vesper. While the latter is making headway as a maker of piezoelectric MEMS microphones, AAC is already established as a staple mic supplier for almost all generations of iPhones, and has a 50% share in the global smartphone market.
MEMS microphones with differential output allow for an almost undistorted signal, even at high SPL.Infineon has developed new MEMS microphones that deliver “a maximum sound pressure level (SPL) around 10dB higher than the best microphones available on the market.” They use a dual back plate solution that can not only deliver a signal-to-noise ratio of 66 dB, but also provides an acoustic overload point of 135dB, which is the SPL where noticeable distortion occurs. Infineon’s engineering team has managed to refine the technology so that the company can deliver MEMS microphones with differential output, allowing for an almost undistorted signal even at high SPLs.
On Vesper’s side, its solutions are piezoelectric, which can make MEMS microphones intrinsically waterproof, dustproof, and particle resistant. Dust can easily infiltrate the tiny mic holes in a smartphone, posing a danger of signal loss and microphone failure. As smartphones come with an array of microphones to form a beam for noise cancellation. A single mic failure caused by particle contamination or other accidents could result in a 90% failure rate. Mic failure makes for the second biggest complaint among smartphone users, right after cracked screens.
Vesper will begin pilot production of its MEMS mics by the end of the second quarter. CEO Crowley is optimistic about the product, because partnering firm AAC "already knows every single customer to go after.” This means smartphones from the second half of the year could boast significantly improved audio recording.