Headphones

Increasingly we're seeing planar magnetic (PM) headphones with single-sided drivers to save weight and size. Last issue it was the Audeze LCD-1, this time around the Aeon 2. Both also have capsules which fold up into the headband to enhance portability, but in other respects the LCD-1 and Aeon 2 are rather different. While both resort to low impedance to retain voltage sensitivity, the LCD-1 is much more successful than the Aeon 2. We recorded an impressive 118.1dB for the former, but Dan Clark Audio's latest creation is a long way adrift at 105.2dB. This is not to say that the Aeon 2 is likely to be incompatible with the usual spectrum of signal sources, both portable and 'fixed' – it isn't – but you may notice that the volume control setting is higher than with other headphones.

As usual with PM drivers, impedance is virtually constant across the audio spectrum so you need have no concerns about changes in frequency response caused by different source impedances. Also typical for PM designs, the Aeon 2 has an extended bass response – but only if those ear-shaped capsules seal well to the head. As we found with the Ether 2, tested when Dan Clark Audio was still MrSpeakers [HFN Jul '19], the Aeon 2 is sensitive to this seal being compromised. Whereas some open-back PM designs shrug off earpad leakage due to spectacles or hair, the Aeon 2 does not – it suffers significant loss in bass output.

The uncorrected frequency responses [Graph 1, below] are par for the course for a PM design in that, as already noted, LF output is extended, and the expected output peak at around 3kHz is less energetic than usually considered necessary for a neutral tonal balance. The shelved-up LF and reticent presence band peak mean that in all three corrected responses [see Graph 2, below] there is a marked bias to lower midrange and bass frequencies, and a distinct paucity of treble. KH