Apple recently invited CNET journalist Patrick Holland to visit the company's specialized labs in Cupertino, where company engineers test and calibrate the audio and video capabilities of iPhone 16 smartphones.
One of the places Holland visited was the so-called long-wave anechoic chamber, where the walls, ceiling, and floor are covered with special sound-absorbing foam wedges to eliminate echo. The facility is used to test the iPhone 16's four microphones, which despite their small size are designed to deliver professional audio quality.
“iPhone is such a ubiquitous recording device, used in so many different settings, that we want to make sure our users can capture their memories in their truest form. We have chosen an approach that combines quality and practicality. Within this framework, we have developed a new microphone component that allows us to provide some of the best acoustic performance in a phone product. At the same time, we developed a feature called Audio Mix, which gives users the flexibility to record different sounds and also gives creative freedom in editing to customize the sound the way you want,“ explains in a conversation with Holland, Apple's senior director of acoustic technologies, Ruchir Dave.
When testing the audio capabilities of its smartphones, Apple uses a complex array of speakers, while the iPhone, mounted on a special stand in the center of the anechoic chamber, rotates, thereby creating a spherical sound profile. This data forms the basis for features like Spatial Audio and Audio Mix, which allow users to customize recorded audio to simulate different types of microphones. In select soundproof studios, Apple compares the playback of recorded sounds with multiple testers to ensure consistent sound quality from iPhone.
A highlight of the tour was a cinema-sized smartphone video testing lab. This room is where Apple engineers calibrate display performance under various lighting conditions. The room features a huge screen that simulates how video looks on iPhone displays, whether viewed in a dark room, office space, or bright sunlight.