By Graham K. Rogers

When the MacBook was introduced last year, one of the main design limitations was the size of the headphone jack. The standard 3.5mm port, plus a little aluminium for practical strength, was the main criterion in design of the thin enclosure. The USB-C connector has a height of 2.6mm. If that alone were used, it would enable some slimming down, although how much more is practical is debatable.

MacBook - Image Courtesy of Apple

A similar question arises with the headphone jack as used in the iPhone. There were some suggestions a few months back that Apple could remove the headphone jack entirely and use the Lightning connector as an all-purpose power and data link that could also carry digital signals for audio. While there was some opposition to this, I see it as a step in the right direction: there would be improvements to digital quality; and it would be possible to reduce the number of components in a device.

There is a lot of sense to this, despite the need for some users to change connectors. Removal of the hardware components within iOS devices necessary for the 3.5mm headphone connector, would save some space. Apple tends to prefer such solutions: the end result is enhanced simplicity; and the saved space can be better used. Apple might use such space to make the iPhone even thinner (although there are practical limits), but space saved can also be used for additional batteries.

This week, Intel has begun to push for the use of USB-C as a replacement for the headphone jack (Tim Hardwick, MacRumors), noting that it could be capable of digital audio transmission: something which Lightning could also accomplish.

Were Apple to remove the headphone jack and switch to Lightning connectors, the solution would be fairly elegant: iPhones and other iOS devices already have these as standard while music content on iOS devices is digital and there is talk of improved quality. Analog output has drawbacks with conversion from a digital format.

iPhone 6s Plus

While USB-C is 8.4mm x 2.6mm, the Lightning connector is 6.7mm x 1.5mm, dimensions which would make a considerable difference to the design of Apple's devices. Remember that some were critical of the replacement of Apple's 30-pin connector by Lightning, suggesting that those awful micro-USB connectors were preferable. I avoid using these with my Nikon as they feel so flimsy.

In its comparison of USB-C and Lightning last year, 9to5 Mac (Seth Weintraub) carries an image of the Nokia N1 that has USB-C. This does not look excessive and USB-C has a number of advantages in the way it carries data and power in two directions, allowing for additional charging solutions.

If Apple were to move to a Lightning-only solution, new users would not be affected as suitable earbuds would be provided with a new iPhone. Those who have 3rd party earphones would need to buy adapters. The same would be true of any switch to the Intel solution and could affect more users were companies like Samsung to remove the headphone jack on its models in favour of USB-C.

Graham K. Rogers teaches at the Faculty of Engineering, Mahidol University in Thailand. He wrote in the Bangkok Post, Database supplement on IT subjects. For the last seven years of Database he wrote a column on Apple and Macs. He is now continuing that in the Bangkok Post supplement, Life.