Headphones

Having remarked the low sensitivity of the HiFiMan Sundara [HFN Jun '19], the same has also to be said of its costlier stablemate, the Arya. At an average for the two capsules of 103.5dB SPL for 1V input, the Arya is actually slightly less sensitive (105.7dB for the Sundara), despite having a lower impedance (29ohm as opposed to 38ohm). So it's possible that some (portable) signal sources might struggle to deliver sufficient peak output capability from the Arya, although its lack of mini-jack compatibility makes this less likely.

As with the Sundara, variation in impedance across the audio band is so small – 28.9 to 29.2ohm – that no significant modification of frequency response will occur with the normal range of headphone amplifier output impedances. Uncorrected frequency responses [Graph 1, below] are typical for a planar magnetic design. Output below 1kHz is largely flat down to low bass frequencies, rolling off below 20Hz (–6dB re. 200Hz). And while there is some response peaking around 3kHz, it isn't sufficient to achieve a neutral tonal balance through the presence band. As a result of these features, the diffuse-field corrected response [green trace, Graph 2 below] suggests that the perceived tonal balance will be perceived as 'warm', and possibly with a lack of lower treble.

On the plus side, the Arya is largely insensitive to poor earpad sealing due to leakage past spectacles or through hair [see Investigation, p28] but, as with all open-back headphones, isolation of external sounds is only significant at high frequencies. As noted in the main text the structure of the Arya is resonant, which manifests itself as peaking in the acoustical crosstalk test at around 3kHz. The CSD waterfall also displays resonance in this range, and there are matching irregularities in the impedance vs. frequency trace [not shown here]. Both also indicate resonances at about 350Hz and 550Hz. KH