MFi Specifications for Lightning Headphones

Last week’s article from the Journal about the next-generation iPhone’s lack of a headphone jack produced as much of the teeth-gnashing as I expected. There are some valid criticisms, I think, of the rumoured change to Lightning and Bluetooth for headphones, but there seems to be some misinformation out there. As much of this subject is still rumoured, that’s understandable; however, some details — particularly with regards to MFi Lightning headphones — are known and documented.

As an example, I saw some concern about a cheapening of the digital-to-analog converter and the amplifier. For instance, Steve Streza:1

Removing the analog headphone port means you’re removing the DAC and the amplifier from the phone into the headphones. This is good news for the high-end, but awful news at the low end. Cheap DACs sound really, really bad, and that’s what you’re going to get in cheap headphones (which is what a lot of high school and college kids who lose their EarPods end up with). But no matter which you get, you will be paying a premium for it in your headphones, so Apple can save a few cents on one of the most commoditized components you’ll find in an iPhone.

According to a 2014 report from 9to5Mac’s Jordan Kahn, the MFi program mandates specific hardware requirements for Lightning headphones:

Apple will allow two configurations for the headphones. Standard Lightning Headphones are described by Apple as using minimum components when paired with a digital-to-analog converter supported by the Lightning Headphone Module. It also has an Advanced Lightning Headphones specification that allows digital audio processing features like active noise cancellation and uses a digital signal processor and digital/analog converter. Manufacturers building the Standard configuration have to use this Wolfson digital-to-analog converter.

The DAC in question — the WM8533 — is a fairly standard DAC that has previously been used in Apple’s Lightning-to-dock connector adapter and it is, by all reviews that I can find, decent.

I don’t mean to pick on Streza here; I saw a similar sentiment from many of those reacting to the news. But it seems like Apple considered the likelihood of headphone manufacturers using cheap and inferior parts, and will use the MFi program to control that. Since the technical details of the MFi specification are confidential, I’m not sure what other base-level requirements Apple may have for Lightning headphones. There’s no way they’re willing to let third parties ruin their standards, though.

Update: While I was drafting this post, Cirrus announced a Lightning headphone development kit. Though the press release doesn’t mention what DAC is used, I’ll note that Cirrus owns Wolfson.

  1. I disagree with Streza’s interpretation of Apple’s motives here. I sincerely doubt they’d do this to “save a few cents”. Even at Apple’s scale, that saves only a few million dollars every year against billions of dollars in profit. ↥︎