Apple will soon allow vendors who design MFi-certified accessories to build support for an obscure but already-existent port in order to ease some of the connectivity and adapter woes associated with Lightning-based headphones. 9to5Mac reported that the company might market UAC, an intermediary in headphone cables, as “Ultra Accessory Connector” (UAC).
Citing sources at Apple, The Verge adds that UAC is an old plug you might have seen with your Nikon DSLR camera rather than a proprietary new connector type from Apple. Apple’s ultimate goal with UAC, The Verge claims, is making Lightning and USB-C work better together rather than replacing them with a brand new I/O port.
The developer preview supplied to accessory designers is light on details regarding the new space-saving connector, but an Apple spokesperson did confirm to Ars Technica that support for UAC is being added to the MFi specification at the request of MFi program licensees, not because Apple is trying to push licensees to support a new kind of proprietary connector.
UAC is Apple’s marketing name for a port that’s being used in some digital cameras. Different vendors call it different names: Mitsumi, for instance, calls it “Ultra Mini Connector” while Nikon refers to it as “UC-E6”. The iPhone maker has offered UAC to MFi vendors as part of a developer preview so they can prepare for the new component.
The non-symmetrical connector has eight pins and measures 2.05mm by 4.85mm, or slightly thinner than USB-C and almost half as wide as both USB-C and Lightning. By comparison, Lightning I/O is 1.5mm thick, 6.73mm wide and 7mm deep.
The Verge explains that UAC would let the firmware in your headphones adjust on the fly, “recognizing whether it’s receiving audio from a Lightning or USB-C connection and playing it back appropriately.” As such, UAC should help with headphone interoperability while easing connectivity and adapter woes commonly associated with MFi-certified Lightning headphones.
Currently, Lightning headphones don’t work on USB-C devices. Likewise, USB-C headphones only work with USB-C audio sources. By inserting UAC in the middle, users will be able to swap between Lightning-to-UAC and USB-C-to-UAC cables with the same pair of headphones.
Apple’s official specification for UAC currently defines both male and female connectors for cables used on headphones. 9to5Mac reports that Apple will let MFi-certified vendors design Lightning to UAC, USB-A to UAC and 3.5mm to UAC adapters.
Apple already provides female Lightning ports for MFi-certified accessories like headphones. For example, the AirPods charging case and the upcoming BeatsX earbuds are outfitted with a Lightning port for charging. Other Beats products have not yet transitioned from micro-USB to Lightning for charging purposes.
Apple’s mobile devices originally used the 30-pin Dock connector, which debuted in the original iPod. After nearly a decade, the Dock connector was succeeded by the reversible Lightning I/O port, first used on 2012 iPhones and iPads.
Image: Apple’s existing Lightning connector.