Measurements
THD+noise plot is fairly good, but a few spikes might be indicative of the hardness I heard in the midrange.
The impedance plot shows a nominally 34 Ohm headphone. The three glitches in both the impedance and phase plot at 440Hz, 700Hz, and 1.7kHz match up with similar features in the frequency response and distortion plots. I suspect we're seeing some modal vibration of the diaphragm at these frequencies.
Isolation plots shows that these are fairly open headphones and responds as expected.
Needing 137mVrms to reach 90dB at the ear, the AR-H1 will play to solid levels from portable devices.
Click on graphs image to download .pdf for closer inspection.
Raw frequency response plots show a flat bass response to 200Hz. I like some emphasis, but bass response on an open headphone is rare. Midrange response from 200Hz to 1kHz is quite uneven. THis isn't necessarily a problem as the HiFiMAN HE1000 also has this character and is a very pleasant headphone to hear, but in this case I did hear these cans as lacking some coherence through the midrange and could get a little hard sounding—especially at high volume. The rise from 1kHz to 3kHz is a little rough, but more importantly should rise about 5dB farther to be on target. This resulted in a distant sound lacking in vocal overtones. Although the curve overall is fairly flat, there is an area between 8kHz and 12kHz that is pretty clearly overemphasized to my ears.
30Hz square wave is slightly swayback but remains above zero over its length. I felt the bass was the best area of performance of these headphones. 300Hz square wave is somewhat ragged looking and indicative of the high frequency splashy sound I heard.
Impulse response is a little better looking though it does ring for a while. Planar magnetics will often do this without too much detriment, in this case however I found it audible.
