Last week my iPhone SE came in. And though she ordered it late, so did my wife’s iPhone 7. While the SE is gloriously understated, and wieldy, the 7 is a return to what I consider Apple’s most horrific modern design. Its largest makeover is the removal of a headphone jack. Next is the smoothing out of its camera hump, a consequence of which is that iPhone 6-compatible cases half cover up the iPhone 7’s camera and flash superstructure.

Its reliance on the lightning to 3,5mm audio dongle equalises output quality across the iDevice line, which is born out in the below loaded and unloaded results. Following them is a brief summary comparison to the iPhone 6 / Lightning to 3,5mm dongle combination.

Relevant RMAA measurements:
RMAA: Apple iPhone 6 24-bit
RMAA: Apple's Lightning to 3,5 mm Headphone Jack Adapter 24-bit

Source: iPhone 7
ADC: Lynx Studio HILO LT-TB
Computer: 2012 27" iMac
Cables: 1,5m Hosa Pro 3,5mm stereo to dual 3-pin XLR (around 8$)

Loads:
NL - no load
SM2 - Earsonics SM2
ES7 - Audio Technica ES7
DT880 - Beyerdynamic DT880/600

24-bit TARGETS and loads +0dB (volume matched to iPhone 6’s maximum).

24-bit summary +0dB (NL, volume matched to iPhone 6’s maximum).

iPhone 6/7 24-bit NL/SM2 and loads +0dB (volume matched to iPhone 6’s maximum).

End words

While inelegant, the dongle certainly does the iPhone - and most compatible iDevices - proud. Noise is next to gone, EMI interference is lower than the discrete circuit in the iPhone 6, and under load, the dongle delivers neutral output unmatched this side of a Chord Mojo. Yes, unloaded THD and jitter results are higher than hitherto iPhones. But are they audible? I doubt it. And under high-stress loads, the iPhone 6 outputs at minimum, twice the distortion. Further, loaded deviation from unloaded results is, bar none, the lowest I've measured.