A new Apple patent suggests the company could use an optical audio transmission from VR headsets to AirPods. Optical audio systems use fiber optic cables and laser light to transmit digital audio signals between two devices. Apple is among the companies exploring alternatives to Bluetooth for audio. “Though freeing in many ways, wireless technology typically offers relatively slow data transmission rates, with 25Mbps being the standard,” CEO of the audio engineering company Voices, David Ciccarelli, told Lifewire in an email interview. “For context, a fast internet connection is considered to be at least 100Mbps. Put simply, this means Bluetooth isn’t an ideal method for transferring large amounts of data, like videos or audio files.”
Better Than Bluetooth?
Apple’s patent (first noted by Patently Apple) is generic, but suggestive. “A system that includes an audio source device configured to obtain audio data of at least one audio channel of a piece of program content,” the patent application reads. “The audio source device has an optical transmitter for transmitting the audio data as an optical signal and a radio frequency (RF) transceiver.” Bluetooth isn’t always ideal for VR, Ciccarelli said, since the radio waves used by the system have a short range. There are three types of Bluetooth, with two types reaching only a 10-meter radius and the widest range being 100 meters. “Being physically close to the main device isn’t always an option, especially with many VR experiences relying on mobile gameplay and encouraging users to move around quite a bit,” he added. The security of Bluetooth is another potential area of concern. “Bluetooth utilizes radio frequencies, which are a lot more difficult to protect than, say, your WiFi connection,” Ciccarelli said. “For that reason, it’s probably best that sensitive or private information isn’t transferred via Bluetooth.” Optical audio transmission has several advantages over Bluetooth. The data transfer rates are faster when compared to many other connection types, Ciccarelli said. Optical audio is also multichannel, meaning it supports 7.1 surround sound or other applications with multiple audio tracks. The limitations of Bluetooth include the small but significant delay (latency) in sending the audio signal from the device to the headphone, which is especially important in gaming applications, Ramani Duraiswami, a computer science professor at the University of Maryland, College Park, who works on audio applications, told Lifewire in an email interview. “Bluetooth at high quality is a drain on a device’s battery,” he added. “Low energy versions of Bluetooth support longer battery life, but cannot support high-quality multichannel audio—they are restricted to stereo.”
No Bluetooth? No Problem
While Bluetooth has its limitations, there are ways to make it sound better. For example, Shure’s AONIC 50 Wireless Noise Canceling Headphones contain the LDAC codec, which the company claims gives users a higher quality sound over generic Bluetooth. There’s also the new Mojo 2, a battery-powered accessory that claims to improve the sound of your wired headphones or speakers when connected to a digital media source. The $725 Mojo 2 lets you adjust the relative volumes of a track’s different audio frequencies. Chord, the company behind the Mojo 2, claims that this process doesn’t degrade the original audio signal. One new smart speaker even lets you ditch the headphone altogether. The Noveto N1 uses facial recognition and other technologies to let you hear private stereo sound without using headphones. The $800 N1 looks like a miniature soundbar for your desk. Noveto’s smart audio beaming technology uses cameras to let you listen to music or any kind of audio while people nearby only hear ambient noise, the company says. But future versions of Bluetooth may keep the aging technology at the top of its game. We’ll likely see lower power, multichannel audio, and potentially video over Bluetooth, Duraiswami said. “Ushering in the next generation of Bluetooth audio is one of the many ways more emphasis is being placed on how society experiences sound,” he added.
